diff --git a/news/distlib.vendor.rst b/news/distlib.vendor.rst
new file mode 100644
index 00000000000..428113e8b67
--- /dev/null
+++ b/news/distlib.vendor.rst
@@ -0,0 +1 @@
+Upgrade distlib to 0.3.9
diff --git a/src/pip/_vendor/distlib/__init__.py b/src/pip/_vendor/distlib/__init__.py
index e999438fe94..bf0d6c6d30e 100644
--- a/src/pip/_vendor/distlib/__init__.py
+++ b/src/pip/_vendor/distlib/__init__.py
@@ -6,7 +6,7 @@
 #
 import logging
 
-__version__ = '0.3.8'
+__version__ = '0.3.9'
 
 
 class DistlibException(Exception):
diff --git a/src/pip/_vendor/distlib/compat.py b/src/pip/_vendor/distlib/compat.py
index e93dc27a3eb..ca561dd2e37 100644
--- a/src/pip/_vendor/distlib/compat.py
+++ b/src/pip/_vendor/distlib/compat.py
@@ -217,8 +217,7 @@ def which(cmd, mode=os.F_OK | os.X_OK, path=None):
         # Additionally check that `file` is not a directory, as on Windows
         # directories pass the os.access check.
         def _access_check(fn, mode):
-            return (os.path.exists(fn) and os.access(fn, mode)
-                    and not os.path.isdir(fn))
+            return (os.path.exists(fn) and os.access(fn, mode) and not os.path.isdir(fn))
 
         # If we're given a path with a directory part, look it up directly rather
         # than referring to PATH directories. This includes checking relative to the
diff --git a/src/pip/_vendor/distlib/database.py b/src/pip/_vendor/distlib/database.py
index eb3765f193b..c0f896a7d85 100644
--- a/src/pip/_vendor/distlib/database.py
+++ b/src/pip/_vendor/distlib/database.py
@@ -20,14 +20,12 @@
 from . import DistlibException, resources
 from .compat import StringIO
 from .version import get_scheme, UnsupportedVersionError
-from .metadata import (Metadata, METADATA_FILENAME, WHEEL_METADATA_FILENAME,
-                       LEGACY_METADATA_FILENAME)
-from .util import (parse_requirement, cached_property, parse_name_and_version,
-                   read_exports, write_exports, CSVReader, CSVWriter)
+from .metadata import (Metadata, METADATA_FILENAME, WHEEL_METADATA_FILENAME, LEGACY_METADATA_FILENAME)
+from .util import (parse_requirement, cached_property, parse_name_and_version, read_exports, write_exports, CSVReader,
+                   CSVWriter)
 
 __all__ = [
-    'Distribution', 'BaseInstalledDistribution', 'InstalledDistribution',
-    'EggInfoDistribution', 'DistributionPath'
+    'Distribution', 'BaseInstalledDistribution', 'InstalledDistribution', 'EggInfoDistribution', 'DistributionPath'
 ]
 
 logger = logging.getLogger(__name__)
@@ -35,8 +33,7 @@
 EXPORTS_FILENAME = 'pydist-exports.json'
 COMMANDS_FILENAME = 'pydist-commands.json'
 
-DIST_FILES = ('INSTALLER', METADATA_FILENAME, 'RECORD', 'REQUESTED',
-              'RESOURCES', EXPORTS_FILENAME, 'SHARED')
+DIST_FILES = ('INSTALLER', METADATA_FILENAME, 'RECORD', 'REQUESTED', 'RESOURCES', EXPORTS_FILENAME, 'SHARED')
 
 DISTINFO_EXT = '.dist-info'
 
@@ -134,13 +131,9 @@ def _yield_distributions(self):
                     continue
                 try:
                     if self._include_dist and entry.endswith(DISTINFO_EXT):
-                        possible_filenames = [
-                            METADATA_FILENAME, WHEEL_METADATA_FILENAME,
-                            LEGACY_METADATA_FILENAME
-                        ]
+                        possible_filenames = [METADATA_FILENAME, WHEEL_METADATA_FILENAME, LEGACY_METADATA_FILENAME]
                         for metadata_filename in possible_filenames:
-                            metadata_path = posixpath.join(
-                                entry, metadata_filename)
+                            metadata_path = posixpath.join(entry, metadata_filename)
                             pydist = finder.find(metadata_path)
                             if pydist:
                                 break
@@ -148,15 +141,11 @@ def _yield_distributions(self):
                             continue
 
                         with contextlib.closing(pydist.as_stream()) as stream:
-                            metadata = Metadata(fileobj=stream,
-                                                scheme='legacy')
+                            metadata = Metadata(fileobj=stream, scheme='legacy')
                         logger.debug('Found %s', r.path)
                         seen.add(r.path)
-                        yield new_dist_class(r.path,
-                                             metadata=metadata,
-                                             env=self)
-                    elif self._include_egg and entry.endswith(
-                            ('.egg-info', '.egg')):
+                        yield new_dist_class(r.path, metadata=metadata, env=self)
+                    elif self._include_egg and entry.endswith(('.egg-info', '.egg')):
                         logger.debug('Found %s', r.path)
                         seen.add(r.path)
                         yield old_dist_class(r.path, self)
@@ -274,8 +263,7 @@ def provides_distribution(self, name, version=None):
             try:
                 matcher = self._scheme.matcher('%s (%s)' % (name, version))
             except ValueError:
-                raise DistlibException('invalid name or version: %r, %r' %
-                                       (name, version))
+                raise DistlibException('invalid name or version: %r, %r' % (name, version))
 
         for dist in self.get_distributions():
             # We hit a problem on Travis where enum34 was installed and doesn't
@@ -390,10 +378,8 @@ def provides(self):
     def _get_requirements(self, req_attr):
         md = self.metadata
         reqts = getattr(md, req_attr)
-        logger.debug('%s: got requirements %r from metadata: %r', self.name,
-                     req_attr, reqts)
-        return set(
-            md.get_requirements(reqts, extras=self.extras, env=self.context))
+        logger.debug('%s: got requirements %r from metadata: %r', self.name, req_attr, reqts)
+        return set(md.get_requirements(reqts, extras=self.extras, env=self.context))
 
     @property
     def run_requires(self):
@@ -469,8 +455,7 @@ def __eq__(self, other):
         if type(other) is not type(self):
             result = False
         else:
-            result = (self.name == other.name and self.version == other.version
-                      and self.source_url == other.source_url)
+            result = (self.name == other.name and self.version == other.version and self.source_url == other.source_url)
         return result
 
     def __hash__(self):
@@ -561,8 +546,7 @@ def __init__(self, path, metadata=None, env=None):
             if r is None:
                 r = finder.find(LEGACY_METADATA_FILENAME)
             if r is None:
-                raise ValueError('no %s found in %s' %
-                                 (METADATA_FILENAME, path))
+                raise ValueError('no %s found in %s' % (METADATA_FILENAME, path))
             with contextlib.closing(r.as_stream()) as stream:
                 metadata = Metadata(fileobj=stream, scheme='legacy')
 
@@ -580,8 +564,7 @@ def __init__(self, path, metadata=None, env=None):
             self.modules = data.splitlines()
 
     def __repr__(self):
-        return '<InstalledDistribution %r %s at %r>' % (
-            self.name, self.version, self.path)
+        return '<InstalledDistribution %r %s at %r>' % (self.name, self.version, self.path)
 
     def __str__(self):
         return "%s %s" % (self.name, self.version)
@@ -703,8 +686,7 @@ def write_installed_files(self, paths, prefix, dry_run=False):
                     size = '%d' % os.path.getsize(path)
                     with open(path, 'rb') as fp:
                         hash_value = self.get_hash(fp.read())
-                if path.startswith(base) or (base_under_prefix
-                                             and path.startswith(prefix)):
+                if path.startswith(base) or (base_under_prefix and path.startswith(prefix)):
                     path = os.path.relpath(path, base)
                 writer.writerow((path, hash_value, size))
 
@@ -746,8 +728,7 @@ def check_installed_files(self):
                     with open(path, 'rb') as f:
                         actual_hash = self.get_hash(f.read(), hasher)
                         if actual_hash != hash_value:
-                            mismatches.append(
-                                (path, 'hash', hash_value, actual_hash))
+                            mismatches.append((path, 'hash', hash_value, actual_hash))
         return mismatches
 
     @cached_property
@@ -829,9 +810,8 @@ def get_distinfo_file(self, path):
             # it's an absolute path?
             distinfo_dirname, path = path.split(os.sep)[-2:]
             if distinfo_dirname != self.path.split(os.sep)[-1]:
-                raise DistlibException(
-                    'dist-info file %r does not belong to the %r %s '
-                    'distribution' % (path, self.name, self.version))
+                raise DistlibException('dist-info file %r does not belong to the %r %s '
+                                       'distribution' % (path, self.name, self.version))
 
         # The file must be relative
         if path not in DIST_FILES:
@@ -857,8 +837,7 @@ def list_distinfo_files(self):
                 yield path
 
     def __eq__(self, other):
-        return (isinstance(other, InstalledDistribution)
-                and self.path == other.path)
+        return (isinstance(other, InstalledDistribution) and self.path == other.path)
 
     # See http://docs.python.org/reference/datamodel#object.__hash__
     __hash__ = object.__hash__
@@ -911,8 +890,7 @@ def parse_requires_data(data):
                 if not line:  # pragma: no cover
                     continue
                 if line.startswith('['):  # pragma: no cover
-                    logger.warning(
-                        'Unexpected line: quitting requirement scan: %r', line)
+                    logger.warning('Unexpected line: quitting requirement scan: %r', line)
                     break
                 r = parse_requirement(line)
                 if not r:  # pragma: no cover
@@ -954,13 +932,11 @@ def parse_requires_path(req_path):
             else:
                 # FIXME handle the case where zipfile is not available
                 zipf = zipimport.zipimporter(path)
-                fileobj = StringIO(
-                    zipf.get_data('EGG-INFO/PKG-INFO').decode('utf8'))
+                fileobj = StringIO(zipf.get_data('EGG-INFO/PKG-INFO').decode('utf8'))
                 metadata = Metadata(fileobj=fileobj, scheme='legacy')
                 try:
                     data = zipf.get_data('EGG-INFO/requires.txt')
-                    tl_data = zipf.get_data('EGG-INFO/top_level.txt').decode(
-                        'utf-8')
+                    tl_data = zipf.get_data('EGG-INFO/top_level.txt').decode('utf-8')
                     requires = parse_requires_data(data.decode('utf-8'))
                 except IOError:
                     requires = None
@@ -990,8 +966,7 @@ def parse_requires_path(req_path):
         return metadata
 
     def __repr__(self):
-        return '<EggInfoDistribution %r %s at %r>' % (self.name, self.version,
-                                                      self.path)
+        return '<EggInfoDistribution %r %s at %r>' % (self.name, self.version, self.path)
 
     def __str__(self):
         return "%s %s" % (self.name, self.version)
@@ -1083,8 +1058,7 @@ def list_distinfo_files(self, absolute=False):
                                 yield line
 
     def __eq__(self, other):
-        return (isinstance(other, EggInfoDistribution)
-                and self.path == other.path)
+        return (isinstance(other, EggInfoDistribution) and self.path == other.path)
 
     # See http://docs.python.org/reference/datamodel#object.__hash__
     __hash__ = object.__hash__
@@ -1184,8 +1158,7 @@ def to_dot(self, f, skip_disconnected=True):
                 disconnected.append(dist)
             for other, label in adjs:
                 if label is not None:
-                    f.write('"%s" -> "%s" [label="%s"]\n' %
-                            (dist.name, other.name, label))
+                    f.write('"%s" -> "%s" [label="%s"]\n' % (dist.name, other.name, label))
                 else:
                     f.write('"%s" -> "%s"\n' % (dist.name, other.name))
         if not skip_disconnected and len(disconnected) > 0:
@@ -1225,8 +1198,7 @@ def topological_sort(self):
             # Remove from the adjacency list of others
             for k, v in alist.items():
                 alist[k] = [(d, r) for d, r in v if d not in to_remove]
-            logger.debug('Moving to result: %s',
-                         ['%s (%s)' % (d.name, d.version) for d in to_remove])
+            logger.debug('Moving to result: %s', ['%s (%s)' % (d.name, d.version) for d in to_remove])
             result.extend(to_remove)
         return result, list(alist.keys())
 
@@ -1261,15 +1233,13 @@ def make_graph(dists, scheme='default'):
 
     # now make the edges
     for dist in dists:
-        requires = (dist.run_requires | dist.meta_requires
-                    | dist.build_requires | dist.dev_requires)
+        requires = (dist.run_requires | dist.meta_requires | dist.build_requires | dist.dev_requires)
         for req in requires:
             try:
                 matcher = scheme.matcher(req)
             except UnsupportedVersionError:
                 # XXX compat-mode if cannot read the version
-                logger.warning('could not read version %r - using name only',
-                               req)
+                logger.warning('could not read version %r - using name only', req)
                 name = req.split()[0]
                 matcher = scheme.matcher(name)
 
diff --git a/src/pip/_vendor/distlib/locators.py b/src/pip/_vendor/distlib/locators.py
index f9f0788fc2a..222c1bf3e90 100644
--- a/src/pip/_vendor/distlib/locators.py
+++ b/src/pip/_vendor/distlib/locators.py
@@ -19,15 +19,12 @@
 import zlib
 
 from . import DistlibException
-from .compat import (urljoin, urlparse, urlunparse, url2pathname, pathname2url,
-                     queue, quote, unescape, build_opener,
-                     HTTPRedirectHandler as BaseRedirectHandler, text_type,
-                     Request, HTTPError, URLError)
+from .compat import (urljoin, urlparse, urlunparse, url2pathname, pathname2url, queue, quote, unescape, build_opener,
+                     HTTPRedirectHandler as BaseRedirectHandler, text_type, Request, HTTPError, URLError)
 from .database import Distribution, DistributionPath, make_dist
 from .metadata import Metadata, MetadataInvalidError
-from .util import (cached_property, ensure_slash, split_filename, get_project_data,
-                   parse_requirement, parse_name_and_version, ServerProxy,
-                   normalize_name)
+from .util import (cached_property, ensure_slash, split_filename, get_project_data, parse_requirement,
+                   parse_name_and_version, ServerProxy, normalize_name)
 from .version import get_scheme, UnsupportedVersionError
 from .wheel import Wheel, is_compatible
 
@@ -58,6 +55,7 @@ class RedirectHandler(BaseRedirectHandler):
     """
     A class to work around a bug in some Python 3.2.x releases.
     """
+
     # There's a bug in the base version for some 3.2.x
     # (e.g. 3.2.2 on Ubuntu Oneiric). If a Location header
     # returns e.g. /abc, it bails because it says the scheme ''
@@ -80,8 +78,7 @@ def http_error_302(self, req, fp, code, msg, headers):
                 headers.replace_header(key, newurl)
             else:
                 headers[key] = newurl
-        return BaseRedirectHandler.http_error_302(self, req, fp, code, msg,
-                                                  headers)
+        return BaseRedirectHandler.http_error_302(self, req, fp, code, msg, headers)
 
     http_error_301 = http_error_303 = http_error_307 = http_error_302
 
@@ -92,7 +89,7 @@ class Locator(object):
     """
     source_extensions = ('.tar.gz', '.tar.bz2', '.tar', '.zip', '.tgz', '.tbz')
     binary_extensions = ('.egg', '.exe', '.whl')
-    excluded_extensions = ('.pdf',)
+    excluded_extensions = ('.pdf', )
 
     # A list of tags indicating which wheels you want to match. The default
     # value of None matches against the tags compatible with the running
@@ -100,7 +97,7 @@ class Locator(object):
     # instance to a list of tuples (pyver, abi, arch) which you want to match.
     wheel_tags = None
 
-    downloadable_extensions = source_extensions + ('.whl',)
+    downloadable_extensions = source_extensions + ('.whl', )
 
     def __init__(self, scheme='default'):
         """
@@ -200,8 +197,7 @@ def score_url(self, url):
         is_downloadable = basename.endswith(self.downloadable_extensions)
         if is_wheel:
             compatible = is_compatible(Wheel(basename), self.wheel_tags)
-        return (t.scheme == 'https', 'pypi.org' in t.netloc,
-                is_downloadable, is_wheel, compatible, basename)
+        return (t.scheme == 'https', 'pypi.org' in t.netloc, is_downloadable, is_wheel, compatible, basename)
 
     def prefer_url(self, url1, url2):
         """
@@ -239,14 +235,14 @@ def convert_url_to_download_info(self, url, project_name):
         If it is, a dictionary is returned with keys "name", "version",
         "filename" and "url"; otherwise, None is returned.
         """
+
         def same_project(name1, name2):
             return normalize_name(name1) == normalize_name(name2)
 
         result = None
         scheme, netloc, path, params, query, frag = urlparse(url)
         if frag.lower().startswith('egg='):  # pragma: no cover
-            logger.debug('%s: version hint in fragment: %r',
-                         project_name, frag)
+            logger.debug('%s: version hint in fragment: %r', project_name, frag)
         m = HASHER_HASH.match(frag)
         if m:
             algo, digest = m.groups()
@@ -270,10 +266,8 @@ def same_project(name1, name2):
                             'name': wheel.name,
                             'version': wheel.version,
                             'filename': wheel.filename,
-                            'url': urlunparse((scheme, netloc, origpath,
-                                               params, query, '')),
-                            'python-version': ', '.join(
-                                ['.'.join(list(v[2:])) for v in wheel.pyver]),
+                            'url': urlunparse((scheme, netloc, origpath, params, query, '')),
+                            'python-version': ', '.join(['.'.join(list(v[2:])) for v in wheel.pyver]),
                         }
             except Exception:  # pragma: no cover
                 logger.warning('invalid path for wheel: %s', path)
@@ -294,8 +288,7 @@ def same_project(name1, name2):
                                 'name': name,
                                 'version': version,
                                 'filename': filename,
-                                'url': urlunparse((scheme, netloc, origpath,
-                                                   params, query, '')),
+                                'url': urlunparse((scheme, netloc, origpath, params, query, '')),
                             }
                             if pyver:  # pragma: no cover
                                 result['python-version'] = pyver
@@ -371,7 +364,7 @@ def locate(self, requirement, prereleases=False):
         self.matcher = matcher = scheme.matcher(r.requirement)
         logger.debug('matcher: %s (%s)', matcher, type(matcher).__name__)
         versions = self.get_project(r.name)
-        if len(versions) > 2:   # urls and digests keys are present
+        if len(versions) > 2:  # urls and digests keys are present
             # sometimes, versions are invalid
             slist = []
             vcls = matcher.version_class
@@ -412,6 +405,7 @@ class PyPIRPCLocator(Locator):
     This locator uses XML-RPC to locate distributions. It therefore
     cannot be used with simple mirrors (that only mirror file content).
     """
+
     def __init__(self, url, **kwargs):
         """
         Initialise an instance.
@@ -461,6 +455,7 @@ class PyPIJSONLocator(Locator):
     This locator uses PyPI's JSON interface. It's very limited in functionality
     and probably not worth using.
     """
+
     def __init__(self, url, **kwargs):
         super(PyPIJSONLocator, self).__init__(**kwargs)
         self.base_url = ensure_slash(url)
@@ -498,7 +493,7 @@ def _get_project(self, name):
             # Now get other releases
             for version, infos in d['releases'].items():
                 if version == md.version:
-                    continue    # already done
+                    continue  # already done
                 omd = Metadata(scheme=self.scheme)
                 omd.name = md.name
                 omd.version = version
@@ -511,6 +506,8 @@ def _get_project(self, name):
                     odist.digests[url] = self._get_digest(info)
                     result['urls'].setdefault(version, set()).add(url)
                     result['digests'][url] = self._get_digest(info)
+
+
 #            for info in urls:
 #                md.source_url = info['url']
 #                dist.digest = self._get_digest(info)
@@ -534,7 +531,8 @@ class Page(object):
     # or immediately followed by a "rel" attribute. The attribute values can be
     # declared with double quotes, single quotes or no quotes - which leads to
     # the length of the expression.
-    _href = re.compile("""
+    _href = re.compile(
+        """
 (rel\\s*=\\s*(?:"(?P<rel1>[^"]*)"|'(?P<rel2>[^']*)'|(?P<rel3>[^>\\s\n]*))\\s+)?
 href\\s*=\\s*(?:"(?P<url1>[^"]*)"|'(?P<url2>[^']*)'|(?P<url3>[^>\\s\n]*))
 (\\s+rel\\s*=\\s*(?:"(?P<rel4>[^"]*)"|'(?P<rel5>[^']*)'|(?P<rel6>[^>\\s\n]*)))?
@@ -561,17 +559,16 @@ def links(self):
         about their "rel" attribute, for determining which ones to treat as
         downloads and which ones to queue for further scraping.
         """
+
         def clean(url):
             "Tidy up an URL."
             scheme, netloc, path, params, query, frag = urlparse(url)
-            return urlunparse((scheme, netloc, quote(path),
-                               params, query, frag))
+            return urlunparse((scheme, netloc, quote(path), params, query, frag))
 
         result = set()
         for match in self._href.finditer(self.data):
             d = match.groupdict('')
-            rel = (d['rel1'] or d['rel2'] or d['rel3'] or
-                   d['rel4'] or d['rel5'] or d['rel6'])
+            rel = (d['rel1'] or d['rel2'] or d['rel3'] or d['rel4'] or d['rel5'] or d['rel6'])
             url = d['url1'] or d['url2'] or d['url3']
             url = urljoin(self.base_url, url)
             url = unescape(url)
@@ -645,7 +642,7 @@ def _wait_threads(self):
         # Note that you need two loops, since you can't say which
         # thread will get each sentinel
         for t in self._threads:
-            self._to_fetch.put(None)    # sentinel
+            self._to_fetch.put(None)  # sentinel
         for t in self._threads:
             t.join()
         self._threads = []
@@ -693,7 +690,7 @@ def _process_download(self, url):
             info = self.convert_url_to_download_info(url, self.project_name)
         logger.debug('process_download: %s -> %s', url, info)
         if info:
-            with self._lock:    # needed because self.result is shared
+            with self._lock:  # needed because self.result is shared
                 self._update_version_data(self.result, info)
         return info
 
@@ -703,8 +700,7 @@ def _should_queue(self, link, referrer, rel):
         particular "rel" attribute should be queued for scraping.
         """
         scheme, netloc, path, _, _, _ = urlparse(link)
-        if path.endswith(self.source_extensions + self.binary_extensions +
-                         self.excluded_extensions):
+        if path.endswith(self.source_extensions + self.binary_extensions + self.excluded_extensions):
             result = False
         elif self.skip_externals and not link.startswith(self.base_url):
             result = False
@@ -722,8 +718,7 @@ def _should_queue(self, link, referrer, rel):
                 result = False
             else:
                 result = True
-        logger.debug('should_queue: %s (%s) from %s -> %s', link, rel,
-                     referrer, result)
+        logger.debug('should_queue: %s (%s) from %s -> %s', link, rel, referrer, result)
         return result
 
     def _fetch(self):
@@ -738,14 +733,13 @@ def _fetch(self):
             try:
                 if url:
                     page = self.get_page(url)
-                    if page is None:    # e.g. after an error
+                    if page is None:  # e.g. after an error
                         continue
                     for link, rel in page.links:
                         if link not in self._seen:
                             try:
                                 self._seen.add(link)
-                                if (not self._process_download(link) and
-                                        self._should_queue(link, url, rel)):
+                                if (not self._process_download(link) and self._should_queue(link, url, rel)):
                                     logger.debug('Queueing %s from %s', link, url)
                                     self._to_fetch.put(link)
                             except MetadataInvalidError:  # e.g. invalid versions
@@ -793,7 +787,7 @@ def get_page(self, url):
                         data = resp.read()
                         encoding = headers.get('Content-Encoding')
                         if encoding:
-                            decoder = self.decoders[encoding]   # fail if not found
+                            decoder = self.decoders[encoding]  # fail if not found
                             data = decoder(data)
                         encoding = 'utf-8'
                         m = CHARSET.search(content_type)
@@ -802,7 +796,7 @@ def get_page(self, url):
                         try:
                             data = data.decode(encoding)
                         except UnicodeError:  # pragma: no cover
-                            data = data.decode('latin-1')    # fallback
+                            data = data.decode('latin-1')  # fallback
                         result = Page(data, final_url)
                         self._page_cache[final_url] = result
                 except HTTPError as e:
@@ -815,7 +809,7 @@ def get_page(self, url):
                 except Exception as e:  # pragma: no cover
                     logger.exception('Fetch failed: %s: %s', url, e)
                 finally:
-                    self._page_cache[url] = result   # even if None (failure)
+                    self._page_cache[url] = result  # even if None (failure)
         return result
 
     _distname_re = re.compile('<a href=[^>]*>([^<]+)<')
@@ -869,9 +863,7 @@ def _get_project(self, name):
             for fn in files:
                 if self.should_include(fn, root):
                     fn = os.path.join(root, fn)
-                    url = urlunparse(('file', '',
-                                      pathname2url(os.path.abspath(fn)),
-                                      '', '', ''))
+                    url = urlunparse(('file', '', pathname2url(os.path.abspath(fn)), '', '', ''))
                     info = self.convert_url_to_download_info(url, name)
                     if info:
                         self._update_version_data(result, info)
@@ -888,9 +880,7 @@ def get_distribution_names(self):
             for fn in files:
                 if self.should_include(fn, root):
                     fn = os.path.join(root, fn)
-                    url = urlunparse(('file', '',
-                                      pathname2url(os.path.abspath(fn)),
-                                      '', '', ''))
+                    url = urlunparse(('file', '', pathname2url(os.path.abspath(fn)), '', '', ''))
                     info = self.convert_url_to_download_info(url, None)
                     if info:
                         result.add(info['name'])
@@ -906,6 +896,7 @@ class JSONLocator(Locator):
     require archive downloads before dependencies can be determined! As you
     might imagine, that can be slow.
     """
+
     def get_distribution_names(self):
         """
         Return all the distribution names known to this locator.
@@ -922,9 +913,9 @@ def _get_project(self, name):
                 # We don't store summary in project metadata as it makes
                 # the data bigger for no benefit during dependency
                 # resolution
-                dist = make_dist(data['name'], info['version'],
-                                 summary=data.get('summary',
-                                                  'Placeholder for summary'),
+                dist = make_dist(data['name'],
+                                 info['version'],
+                                 summary=data.get('summary', 'Placeholder for summary'),
                                  scheme=self.scheme)
                 md = dist.metadata
                 md.source_url = info['url']
@@ -943,6 +934,7 @@ class DistPathLocator(Locator):
     This locator finds installed distributions in a path. It can be useful for
     adding to an :class:`AggregatingLocator`.
     """
+
     def __init__(self, distpath, **kwargs):
         """
         Initialise an instance.
@@ -960,8 +952,12 @@ def _get_project(self, name):
         else:
             result = {
                 dist.version: dist,
-                'urls': {dist.version: set([dist.source_url])},
-                'digests': {dist.version: set([None])}
+                'urls': {
+                    dist.version: set([dist.source_url])
+                },
+                'digests': {
+                    dist.version: set([None])
+                }
             }
         return result
 
@@ -970,6 +966,7 @@ class AggregatingLocator(Locator):
     """
     This class allows you to chain and/or merge a list of locators.
     """
+
     def __init__(self, *locators, **kwargs):
         """
         Initialise an instance.
@@ -1058,10 +1055,9 @@ def get_distribution_names(self):
 # We use a legacy scheme simply because most of the dists on PyPI use legacy
 # versions which don't conform to PEP 440.
 default_locator = AggregatingLocator(
-                    # JSONLocator(), # don't use as PEP 426 is withdrawn
-                    SimpleScrapingLocator('https://pypi.org/simple/',
-                                          timeout=3.0),
-                    scheme='legacy')
+    # JSONLocator(), # don't use as PEP 426 is withdrawn
+    SimpleScrapingLocator('https://pypi.org/simple/', timeout=3.0),
+    scheme='legacy')
 
 locate = default_locator.locate
 
@@ -1137,7 +1133,7 @@ def find_providers(self, reqt):
         :return: A set of distribution which can fulfill the requirement.
         """
         matcher = self.get_matcher(reqt)
-        name = matcher.key   # case-insensitive
+        name = matcher.key  # case-insensitive
         result = set()
         provided = self.provided
         if name in provided:
@@ -1179,8 +1175,7 @@ def try_to_replace(self, provider, other, problems):
                 unmatched.add(s)
         if unmatched:
             # can't replace other with provider
-            problems.add(('cantreplace', provider, other,
-                          frozenset(unmatched)))
+            problems.add(('cantreplace', provider, other, frozenset(unmatched)))
             result = False
         else:
             # can replace other with provider
@@ -1233,8 +1228,7 @@ def find(self, requirement, meta_extras=None, prereleases=False):
             dist = odist = requirement
             logger.debug('passed %s as requirement', odist)
         else:
-            dist = odist = self.locator.locate(requirement,
-                                               prereleases=prereleases)
+            dist = odist = self.locator.locate(requirement, prereleases=prereleases)
             if dist is None:
                 raise DistlibException('Unable to locate %r' % requirement)
             logger.debug('located %s', odist)
@@ -1244,7 +1238,7 @@ def find(self, requirement, meta_extras=None, prereleases=False):
         install_dists = set([odist])
         while todo:
             dist = todo.pop()
-            name = dist.key     # case-insensitive
+            name = dist.key  # case-insensitive
             if name not in self.dists_by_name:
                 self.add_distribution(dist)
             else:
@@ -1281,8 +1275,7 @@ def find(self, requirement, meta_extras=None, prereleases=False):
                         providers.add(provider)
                         if r in ireqts and dist in install_dists:
                             install_dists.add(provider)
-                            logger.debug('Adding %s to install_dists',
-                                         provider.name_and_version)
+                            logger.debug('Adding %s to install_dists', provider.name_and_version)
                 for p in providers:
                     name = p.key
                     if name not in self.dists_by_name:
@@ -1297,7 +1290,6 @@ def find(self, requirement, meta_extras=None, prereleases=False):
         for dist in dists:
             dist.build_time_dependency = dist not in install_dists
             if dist.build_time_dependency:
-                logger.debug('%s is a build-time dependency only.',
-                             dist.name_and_version)
+                logger.debug('%s is a build-time dependency only.', dist.name_and_version)
         logger.debug('find done for %s', odist)
         return dists, problems
diff --git a/src/pip/_vendor/distlib/markers.py b/src/pip/_vendor/distlib/markers.py
index 1514d460e70..3f5632be47c 100644
--- a/src/pip/_vendor/distlib/markers.py
+++ b/src/pip/_vendor/distlib/markers.py
@@ -23,8 +23,7 @@
 
 __all__ = ['interpret']
 
-_VERSION_PATTERN = re.compile(
-    r'((\d+(\.\d+)*\w*)|\'(\d+(\.\d+)*\w*)\'|\"(\d+(\.\d+)*\w*)\")')
+_VERSION_PATTERN = re.compile(r'((\d+(\.\d+)*\w*)|\'(\d+(\.\d+)*\w*)\'|\"(\d+(\.\d+)*\w*)\")')
 _VERSION_MARKERS = {'python_version', 'python_full_version'}
 
 
@@ -82,13 +81,12 @@ def evaluate(self, expr, context):
             elhs = expr['lhs']
             erhs = expr['rhs']
             if _is_literal(expr['lhs']) and _is_literal(expr['rhs']):
-                raise SyntaxError('invalid comparison: %s %s %s' %
-                                  (elhs, op, erhs))
+                raise SyntaxError('invalid comparison: %s %s %s' % (elhs, op, erhs))
 
             lhs = self.evaluate(elhs, context)
             rhs = self.evaluate(erhs, context)
-            if ((_is_version_marker(elhs) or _is_version_marker(erhs))
-                    and op in ('<', '<=', '>', '>=', '===', '==', '!=', '~=')):
+            if ((_is_version_marker(elhs) or _is_version_marker(erhs)) and
+                    op in ('<', '<=', '>', '>=', '===', '==', '!=', '~=')):
                 lhs = LV(lhs)
                 rhs = LV(rhs)
             elif _is_version_marker(elhs) and op in ('in', 'not in'):
@@ -111,8 +109,7 @@ def format_full_version(info):
         return version
 
     if hasattr(sys, 'implementation'):
-        implementation_version = format_full_version(
-            sys.implementation.version)
+        implementation_version = format_full_version(sys.implementation.version)
         implementation_name = sys.implementation.name
     else:
         implementation_version = '0'
@@ -156,11 +153,9 @@ def interpret(marker, execution_context=None):
     try:
         expr, rest = parse_marker(marker)
     except Exception as e:
-        raise SyntaxError('Unable to interpret marker syntax: %s: %s' %
-                          (marker, e))
+        raise SyntaxError('Unable to interpret marker syntax: %s: %s' % (marker, e))
     if rest and rest[0] != '#':
-        raise SyntaxError('unexpected trailing data in marker: %s: %s' %
-                          (marker, rest))
+        raise SyntaxError('unexpected trailing data in marker: %s: %s' % (marker, rest))
     context = dict(DEFAULT_CONTEXT)
     if execution_context:
         context.update(execution_context)
diff --git a/src/pip/_vendor/distlib/metadata.py b/src/pip/_vendor/distlib/metadata.py
index 7189aeef229..ce9a34b3e24 100644
--- a/src/pip/_vendor/distlib/metadata.py
+++ b/src/pip/_vendor/distlib/metadata.py
@@ -15,7 +15,6 @@
 import logging
 import re
 
-
 from . import DistlibException, __version__
 from .compat import StringIO, string_types, text_type
 from .markers import interpret
@@ -40,6 +39,7 @@ class MetadataUnrecognizedVersionError(DistlibException):
 class MetadataInvalidError(DistlibException):
     """A metadata value is invalid"""
 
+
 # public API of this module
 __all__ = ['Metadata', 'PKG_INFO_ENCODING', 'PKG_INFO_PREFERRED_VERSION']
 
@@ -52,53 +52,38 @@ class MetadataInvalidError(DistlibException):
 
 _LINE_PREFIX_1_2 = re.compile('\n       \\|')
 _LINE_PREFIX_PRE_1_2 = re.compile('\n        ')
-_241_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform',
-               'Summary', 'Description',
-               'Keywords', 'Home-page', 'Author', 'Author-email',
-               'License')
-
-_314_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform',
-               'Supported-Platform', 'Summary', 'Description',
-               'Keywords', 'Home-page', 'Author', 'Author-email',
-               'License', 'Classifier', 'Download-URL', 'Obsoletes',
+_241_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform', 'Summary', 'Description', 'Keywords', 'Home-page',
+               'Author', 'Author-email', 'License')
+
+_314_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform', 'Supported-Platform', 'Summary', 'Description',
+               'Keywords', 'Home-page', 'Author', 'Author-email', 'License', 'Classifier', 'Download-URL', 'Obsoletes',
                'Provides', 'Requires')
 
-_314_MARKERS = ('Obsoletes', 'Provides', 'Requires', 'Classifier',
-                'Download-URL')
+_314_MARKERS = ('Obsoletes', 'Provides', 'Requires', 'Classifier', 'Download-URL')
 
-_345_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform',
-               'Supported-Platform', 'Summary', 'Description',
-               'Keywords', 'Home-page', 'Author', 'Author-email',
-               'Maintainer', 'Maintainer-email', 'License',
-               'Classifier', 'Download-URL', 'Obsoletes-Dist',
-               'Project-URL', 'Provides-Dist', 'Requires-Dist',
+_345_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform', 'Supported-Platform', 'Summary', 'Description',
+               'Keywords', 'Home-page', 'Author', 'Author-email', 'Maintainer', 'Maintainer-email', 'License',
+               'Classifier', 'Download-URL', 'Obsoletes-Dist', 'Project-URL', 'Provides-Dist', 'Requires-Dist',
                'Requires-Python', 'Requires-External')
 
-_345_MARKERS = ('Provides-Dist', 'Requires-Dist', 'Requires-Python',
-                'Obsoletes-Dist', 'Requires-External', 'Maintainer',
-                'Maintainer-email', 'Project-URL')
+_345_MARKERS = ('Provides-Dist', 'Requires-Dist', 'Requires-Python', 'Obsoletes-Dist', 'Requires-External',
+                'Maintainer', 'Maintainer-email', 'Project-URL')
 
-_426_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform',
-               'Supported-Platform', 'Summary', 'Description',
-               'Keywords', 'Home-page', 'Author', 'Author-email',
-               'Maintainer', 'Maintainer-email', 'License',
-               'Classifier', 'Download-URL', 'Obsoletes-Dist',
-               'Project-URL', 'Provides-Dist', 'Requires-Dist',
-               'Requires-Python', 'Requires-External', 'Private-Version',
-               'Obsoleted-By', 'Setup-Requires-Dist', 'Extension',
-               'Provides-Extra')
+_426_FIELDS = ('Metadata-Version', 'Name', 'Version', 'Platform', 'Supported-Platform', 'Summary', 'Description',
+               'Keywords', 'Home-page', 'Author', 'Author-email', 'Maintainer', 'Maintainer-email', 'License',
+               'Classifier', 'Download-URL', 'Obsoletes-Dist', 'Project-URL', 'Provides-Dist', 'Requires-Dist',
+               'Requires-Python', 'Requires-External', 'Private-Version', 'Obsoleted-By', 'Setup-Requires-Dist',
+               'Extension', 'Provides-Extra')
 
-_426_MARKERS = ('Private-Version', 'Provides-Extra', 'Obsoleted-By',
-                'Setup-Requires-Dist', 'Extension')
+_426_MARKERS = ('Private-Version', 'Provides-Extra', 'Obsoleted-By', 'Setup-Requires-Dist', 'Extension')
 
 # See issue #106: Sometimes 'Requires' and 'Provides' occur wrongly in
 # the metadata. Include them in the tuple literal below to allow them
 # (for now).
 # Ditto for Obsoletes - see issue #140.
-_566_FIELDS = _426_FIELDS + ('Description-Content-Type',
-                             'Requires', 'Provides', 'Obsoletes')
+_566_FIELDS = _426_FIELDS + ('Description-Content-Type', 'Requires', 'Provides', 'Obsoletes')
 
-_566_MARKERS = ('Description-Content-Type',)
+_566_MARKERS = ('Description-Content-Type', )
 
 _643_MARKERS = ('Dynamic', 'License-File')
 
@@ -135,6 +120,7 @@ def _version2fieldlist(version):
 
 def _best_version(fields):
     """Detect the best version depending on the fields used."""
+
     def _has_marker(keys, markers):
         return any(marker in keys for marker in markers)
 
@@ -163,12 +149,12 @@ def _has_marker(keys, markers):
             possible_versions.remove('2.2')
             logger.debug('Removed 2.2 due to %s', key)
         # if key not in _426_FIELDS and '2.0' in possible_versions:
-            # possible_versions.remove('2.0')
-            # logger.debug('Removed 2.0 due to %s', key)
+        # possible_versions.remove('2.0')
+        # logger.debug('Removed 2.0 due to %s', key)
 
     # possible_version contains qualified versions
     if len(possible_versions) == 1:
-        return possible_versions[0]   # found !
+        return possible_versions[0]  # found !
     elif len(possible_versions) == 0:
         logger.debug('Out of options - unknown metadata set: %s', fields)
         raise MetadataConflictError('Unknown metadata set')
@@ -199,28 +185,25 @@ def _has_marker(keys, markers):
     if is_2_1:
         return '2.1'
     # if is_2_2:
-        # return '2.2'
+    # return '2.2'
 
     return '2.2'
 
+
 # This follows the rules about transforming keys as described in
 # https://www.python.org/dev/peps/pep-0566/#id17
-_ATTR2FIELD = {
-    name.lower().replace("-", "_"): name for name in _ALL_FIELDS
-}
+_ATTR2FIELD = {name.lower().replace("-", "_"): name for name in _ALL_FIELDS}
 _FIELD2ATTR = {field: attr for attr, field in _ATTR2FIELD.items()}
 
 _PREDICATE_FIELDS = ('Requires-Dist', 'Obsoletes-Dist', 'Provides-Dist')
-_VERSIONS_FIELDS = ('Requires-Python',)
-_VERSION_FIELDS = ('Version',)
-_LISTFIELDS = ('Platform', 'Classifier', 'Obsoletes',
-               'Requires', 'Provides', 'Obsoletes-Dist',
-               'Provides-Dist', 'Requires-Dist', 'Requires-External',
-               'Project-URL', 'Supported-Platform', 'Setup-Requires-Dist',
+_VERSIONS_FIELDS = ('Requires-Python', )
+_VERSION_FIELDS = ('Version', )
+_LISTFIELDS = ('Platform', 'Classifier', 'Obsoletes', 'Requires', 'Provides', 'Obsoletes-Dist', 'Provides-Dist',
+               'Requires-Dist', 'Requires-External', 'Project-URL', 'Supported-Platform', 'Setup-Requires-Dist',
                'Provides-Extra', 'Extension', 'License-File')
-_LISTTUPLEFIELDS = ('Project-URL',)
+_LISTTUPLEFIELDS = ('Project-URL', )
 
-_ELEMENTSFIELD = ('Keywords',)
+_ELEMENTSFIELD = ('Keywords', )
 
 _UNICODEFIELDS = ('Author', 'Maintainer', 'Summary', 'Description')
 
@@ -252,10 +235,10 @@ class LegacyMetadata(object):
     - *mapping* is a dict-like object
     - *scheme* is a version scheme name
     """
+
     # TODO document the mapping API and UNKNOWN default key
 
-    def __init__(self, path=None, fileobj=None, mapping=None,
-                 scheme='default'):
+    def __init__(self, path=None, fileobj=None, mapping=None, scheme='default'):
         if [path, fileobj, mapping].count(None) < 2:
             raise TypeError('path, fileobj and mapping are exclusive')
         self._fields = {}
@@ -290,8 +273,7 @@ def __delitem__(self, name):
             raise KeyError(name)
 
     def __contains__(self, name):
-        return (name in self._fields or
-                self._convert_name(name) in self._fields)
+        return (name in self._fields or self._convert_name(name) in self._fields)
 
     def _convert_name(self, name):
         if name in _ALL_FIELDS:
@@ -319,12 +301,12 @@ def __getattr__(self, name):
     # Public API
     #
 
-#    dependencies = property(_get_dependencies, _set_dependencies)
-
     def get_fullname(self, filesafe=False):
-        """Return the distribution name with version.
+        """
+        Return the distribution name with version.
 
-        If filesafe is true, return a filename-escaped form."""
+        If filesafe is true, return a filename-escaped form.
+        """
         return _get_name_and_version(self['Name'], self['Version'], filesafe)
 
     def is_field(self, name):
@@ -415,6 +397,7 @@ def update(self, other=None, **kwargs):
         Keys that don't match a metadata field or that have an empty value are
         dropped.
         """
+
         def _set(key, value):
             if key in _ATTR2FIELD and value:
                 self.set(self._convert_name(key), value)
@@ -437,14 +420,12 @@ def set(self, name, value):
         """Control then set a metadata field."""
         name = self._convert_name(name)
 
-        if ((name in _ELEMENTSFIELD or name == 'Platform') and
-            not isinstance(value, (list, tuple))):
+        if ((name in _ELEMENTSFIELD or name == 'Platform') and not isinstance(value, (list, tuple))):
             if isinstance(value, string_types):
                 value = [v.strip() for v in value.split(',')]
             else:
                 value = []
-        elif (name in _LISTFIELDS and
-              not isinstance(value, (list, tuple))):
+        elif (name in _LISTFIELDS and not isinstance(value, (list, tuple))):
             if isinstance(value, string_types):
                 value = [value]
             else:
@@ -458,18 +439,14 @@ def set(self, name, value):
                 for v in value:
                     # check that the values are valid
                     if not scheme.is_valid_matcher(v.split(';')[0]):
-                        logger.warning(
-                            "'%s': '%s' is not valid (field '%s')",
-                            project_name, v, name)
+                        logger.warning("'%s': '%s' is not valid (field '%s')", project_name, v, name)
             # FIXME this rejects UNKNOWN, is that right?
             elif name in _VERSIONS_FIELDS and value is not None:
                 if not scheme.is_valid_constraint_list(value):
-                    logger.warning("'%s': '%s' is not a valid version (field '%s')",
-                                   project_name, value, name)
+                    logger.warning("'%s': '%s' is not a valid version (field '%s')", project_name, value, name)
             elif name in _VERSION_FIELDS and value is not None:
                 if not scheme.is_valid_version(value):
-                    logger.warning("'%s': '%s' is not a valid version (field '%s')",
-                                   project_name, value, name)
+                    logger.warning("'%s': '%s' is not a valid version (field '%s')", project_name, value, name)
 
         if name in _UNICODEFIELDS:
             if name == 'Description':
@@ -539,10 +516,8 @@ def are_valid_constraints(value):
             return True
 
         for fields, controller in ((_PREDICATE_FIELDS, are_valid_constraints),
-                                   (_VERSIONS_FIELDS,
-                                    scheme.is_valid_constraint_list),
-                                   (_VERSION_FIELDS,
-                                    scheme.is_valid_version)):
+                                   (_VERSIONS_FIELDS, scheme.is_valid_constraint_list), (_VERSION_FIELDS,
+                                                                                         scheme.is_valid_version)):
             for field in fields:
                 value = self.get(field, None)
                 if value is not None and not controller(value):
@@ -598,8 +573,7 @@ def items(self):
         return [(key, self[key]) for key in self.keys()]
 
     def __repr__(self):
-        return '<%s %s %s>' % (self.__class__.__name__, self.name,
-                               self.version)
+        return '<%s %s %s>' % (self.__class__.__name__, self.name, self.version)
 
 
 METADATA_FILENAME = 'pydist.json'
@@ -631,7 +605,7 @@ class Metadata(object):
     MANDATORY_KEYS = {
         'name': (),
         'version': (),
-        'summary': ('legacy',),
+        'summary': ('legacy', ),
     }
 
     INDEX_KEYS = ('name version license summary description author '
@@ -644,22 +618,21 @@ class Metadata(object):
 
     SYNTAX_VALIDATORS = {
         'metadata_version': (METADATA_VERSION_MATCHER, ()),
-        'name': (NAME_MATCHER, ('legacy',)),
-        'version': (VERSION_MATCHER, ('legacy',)),
-        'summary': (SUMMARY_MATCHER, ('legacy',)),
-        'dynamic': (FIELDNAME_MATCHER, ('legacy',)),
+        'name': (NAME_MATCHER, ('legacy', )),
+        'version': (VERSION_MATCHER, ('legacy', )),
+        'summary': (SUMMARY_MATCHER, ('legacy', )),
+        'dynamic': (FIELDNAME_MATCHER, ('legacy', )),
     }
 
     __slots__ = ('_legacy', '_data', 'scheme')
 
-    def __init__(self, path=None, fileobj=None, mapping=None,
-                 scheme='default'):
+    def __init__(self, path=None, fileobj=None, mapping=None, scheme='default'):
         if [path, fileobj, mapping].count(None) < 2:
             raise TypeError('path, fileobj and mapping are exclusive')
         self._legacy = None
         self._data = None
         self.scheme = scheme
-        #import pdb; pdb.set_trace()
+        # import pdb; pdb.set_trace()
         if mapping is not None:
             try:
                 self._validate_mapping(mapping, scheme)
@@ -693,8 +666,7 @@ def __init__(self, path=None, fileobj=None, mapping=None,
                     # The ValueError comes from the json.load - if that
                     # succeeds and we get a validation error, we want
                     # that to propagate
-                    self._legacy = LegacyMetadata(fileobj=StringIO(data),
-                                                  scheme=scheme)
+                    self._legacy = LegacyMetadata(fileobj=StringIO(data), scheme=scheme)
                     self.validate()
 
     common_keys = set(('name', 'version', 'license', 'keywords', 'summary'))
@@ -732,8 +704,7 @@ def __getattribute__(self, key):
                     result = self._legacy.get(lk)
             else:
                 value = None if maker is None else maker()
-                if key not in ('commands', 'exports', 'modules', 'namespaces',
-                               'classifiers'):
+                if key not in ('commands', 'exports', 'modules', 'namespaces', 'classifiers'):
                     result = self._data.get(key, value)
                 else:
                     # special cases for PEP 459
@@ -770,8 +741,7 @@ def _validate_value(self, key, value, scheme=None):
                 m = pattern.match(value)
                 if not m:
                     raise MetadataInvalidError("'%s' is an invalid value for "
-                                               "the '%s' property" % (value,
-                                                                    key))
+                                               "the '%s' property" % (value, key))
 
     def __setattr__(self, key, value):
         self._validate_value(key, value)
@@ -783,8 +753,7 @@ def __setattr__(self, key, value):
                 if lk is None:
                     raise NotImplementedError
                 self._legacy[lk] = value
-            elif key not in ('commands', 'exports', 'modules', 'namespaces',
-                             'classifiers'):
+            elif key not in ('commands', 'exports', 'modules', 'namespaces', 'classifiers'):
                 self._data[key] = value
             else:
                 # special cases for PEP 459
@@ -872,8 +841,7 @@ def get_requirements(self, reqts, extras=None, env=None):
                     # A recursive call, but it should terminate since 'test'
                     # has been removed from the extras
                     reqts = self._data.get('%s_requires' % key, [])
-                    result.extend(self.get_requirements(reqts, extras=extras,
-                                                        env=env))
+                    result.extend(self.get_requirements(reqts, extras=extras, env=env))
         return result
 
     @property
@@ -914,8 +882,7 @@ def validate(self):
         if self._legacy:
             missing, warnings = self._legacy.check(True)
             if missing or warnings:
-                logger.warning('Metadata: missing: %s, warnings: %s',
-                               missing, warnings)
+                logger.warning('Metadata: missing: %s, warnings: %s', missing, warnings)
         else:
             self._validate_mapping(self._data, self.scheme)
 
@@ -932,9 +899,8 @@ def _from_legacy(self):
             'metadata_version': self.METADATA_VERSION,
             'generator': self.GENERATOR,
         }
-        lmd = self._legacy.todict(True)     # skip missing ones
-        for k in ('name', 'version', 'license', 'summary', 'description',
-                  'classifier'):
+        lmd = self._legacy.todict(True)  # skip missing ones
+        for k in ('name', 'version', 'license', 'summary', 'description', 'classifier'):
             if k in lmd:
                 if k == 'classifier':
                     nk = 'classifiers'
@@ -945,14 +911,13 @@ def _from_legacy(self):
         if kw == ['']:
             kw = []
         result['keywords'] = kw
-        keys = (('requires_dist', 'run_requires'),
-                ('setup_requires_dist', 'build_requires'))
+        keys = (('requires_dist', 'run_requires'), ('setup_requires_dist', 'build_requires'))
         for ok, nk in keys:
             if ok in lmd and lmd[ok]:
                 result[nk] = [{'requires': lmd[ok]}]
         result['provides'] = self.provides
-        author = {}
-        maintainer = {}
+        # author = {}
+        # maintainer = {}
         return result
 
     LEGACY_MAPPING = {
@@ -969,6 +934,7 @@ def _from_legacy(self):
     }
 
     def _to_legacy(self):
+
         def process_entries(entries):
             reqts = set()
             for e in entries:
@@ -1037,12 +1003,10 @@ def write(self, path=None, fileobj=None, legacy=False, skip_unknown=True):
             else:
                 d = self._data
             if fileobj:
-                json.dump(d, fileobj, ensure_ascii=True, indent=2,
-                          sort_keys=True)
+                json.dump(d, fileobj, ensure_ascii=True, indent=2, sort_keys=True)
             else:
                 with codecs.open(path, 'w', 'utf-8') as f:
-                    json.dump(d, f, ensure_ascii=True, indent=2,
-                              sort_keys=True)
+                    json.dump(d, f, ensure_ascii=True, indent=2, sort_keys=True)
 
     def add_requirements(self, requirements):
         if self._legacy:
@@ -1055,7 +1019,7 @@ def add_requirements(self, requirements):
                     always = entry
                     break
             if always is None:
-                always = { 'requires': requirements }
+                always = {'requires': requirements}
                 run_requires.insert(0, always)
             else:
                 rset = set(always['requires']) | set(requirements)
@@ -1064,5 +1028,4 @@ def add_requirements(self, requirements):
     def __repr__(self):
         name = self.name or '(no name)'
         version = self.version or 'no version'
-        return '<%s %s %s (%s)>' % (self.__class__.__name__,
-                                    self.metadata_version, name, version)
+        return '<%s %s %s (%s)>' % (self.__class__.__name__, self.metadata_version, name, version)
diff --git a/src/pip/_vendor/distlib/scripts.py b/src/pip/_vendor/distlib/scripts.py
index 0982e6b726e..b1fc705b7e6 100644
--- a/src/pip/_vendor/distlib/scripts.py
+++ b/src/pip/_vendor/distlib/scripts.py
@@ -15,8 +15,7 @@
 
 from .compat import sysconfig, detect_encoding, ZipFile
 from .resources import finder
-from .util import (FileOperator, get_export_entry, convert_path,
-                   get_executable, get_platform, in_venv)
+from .util import (FileOperator, get_export_entry, convert_path, get_executable, get_platform, in_venv)
 
 logger = logging.getLogger(__name__)
 
@@ -57,15 +56,16 @@
 # location where it was imported from. So we load everything into memory in
 # advance.
 
-# Issue 31: don't hardcode an absolute package name, but
-# determine it relative to the current package
-distlib_package = __name__.rsplit('.', 1)[0]
+if os.name == 'nt' or (os.name == 'java' and os._name == 'nt'):
+    # Issue 31: don't hardcode an absolute package name, but
+    # determine it relative to the current package
+    DISTLIB_PACKAGE = __name__.rsplit('.', 1)[0]
 
-WRAPPERS = {
-    r.name: r.bytes
-    for r in finder(distlib_package).iterator("")
-    if r.name.endswith(".exe")
-}
+    WRAPPERS = {
+        r.name: r.bytes
+        for r in finder(DISTLIB_PACKAGE).iterator("")
+        if r.name.endswith(".exe")
+    }
 
 
 def enquote_executable(executable):
@@ -97,25 +97,18 @@ class ScriptMaker(object):
 
     executable = None  # for shebangs
 
-    def __init__(self,
-                 source_dir,
-                 target_dir,
-                 add_launchers=True,
-                 dry_run=False,
-                 fileop=None):
+    def __init__(self, source_dir, target_dir, add_launchers=True, dry_run=False, fileop=None):
         self.source_dir = source_dir
         self.target_dir = target_dir
         self.add_launchers = add_launchers
         self.force = False
         self.clobber = False
         # It only makes sense to set mode bits on POSIX.
-        self.set_mode = (os.name == 'posix') or (os.name == 'java'
-                                                 and os._name == 'posix')
+        self.set_mode = (os.name == 'posix') or (os.name == 'java' and os._name == 'posix')
         self.variants = set(('', 'X.Y'))
         self._fileop = fileop or FileOperator(dry_run)
 
-        self._is_nt = os.name == 'nt' or (os.name == 'java'
-                                          and os._name == 'nt')
+        self._is_nt = os.name == 'nt' or (os.name == 'java' and os._name == 'nt')
         self.version_info = sys.version_info
 
     def _get_alternate_executable(self, executable, options):
@@ -177,15 +170,14 @@ def _build_shebang(self, executable, post_interp):
                 max_shebang_length = 512
             else:
                 max_shebang_length = 127
-            simple_shebang = ((b' ' not in executable)
-                              and (shebang_length <= max_shebang_length))
+            simple_shebang = ((b' ' not in executable) and (shebang_length <= max_shebang_length))
 
         if simple_shebang:
             result = b'#!' + executable + post_interp + b'\n'
         else:
             result = b'#!/bin/sh\n'
             result += b"'''exec' " + executable + post_interp + b' "$0" "$@"\n'
-            result += b"' '''"
+            result += b"' '''\n"
         return result
 
     def _get_shebang(self, encoding, post_interp=b'', options=None):
@@ -196,21 +188,17 @@ def _get_shebang(self, encoding, post_interp=b'', options=None):
         elif not sysconfig.is_python_build():
             executable = get_executable()
         elif in_venv():  # pragma: no cover
-            executable = os.path.join(
-                sysconfig.get_path('scripts'),
-                'python%s' % sysconfig.get_config_var('EXE'))
+            executable = os.path.join(sysconfig.get_path('scripts'), 'python%s' % sysconfig.get_config_var('EXE'))
         else:  # pragma: no cover
             if os.name == 'nt':
                 # for Python builds from source on Windows, no Python executables with
                 # a version suffix are created, so we use python.exe
-                executable = os.path.join(
-                    sysconfig.get_config_var('BINDIR'),
-                    'python%s' % (sysconfig.get_config_var('EXE')))
+                executable = os.path.join(sysconfig.get_config_var('BINDIR'),
+                                          'python%s' % (sysconfig.get_config_var('EXE')))
             else:
                 executable = os.path.join(
                     sysconfig.get_config_var('BINDIR'),
-                    'python%s%s' % (sysconfig.get_config_var('VERSION'),
-                                    sysconfig.get_config_var('EXE')))
+                    'python%s%s' % (sysconfig.get_config_var('VERSION'), sysconfig.get_config_var('EXE')))
         if options:
             executable = self._get_alternate_executable(executable, options)
 
@@ -234,8 +222,8 @@ def _get_shebang(self, encoding, post_interp=b'', options=None):
         # check that the shebang is decodable using utf-8.
         executable = executable.encode('utf-8')
         # in case of IronPython, play safe and enable frames support
-        if (sys.platform == 'cli' and '-X:Frames' not in post_interp
-                and '-X:FullFrames' not in post_interp):  # pragma: no cover
+        if (sys.platform == 'cli' and '-X:Frames' not in post_interp and
+                '-X:FullFrames' not in post_interp):  # pragma: no cover
             post_interp += b' -X:Frames'
         shebang = self._build_shebang(executable, post_interp)
         # Python parser starts to read a script using UTF-8 until
@@ -246,8 +234,7 @@ def _get_shebang(self, encoding, post_interp=b'', options=None):
         try:
             shebang.decode('utf-8')
         except UnicodeDecodeError:  # pragma: no cover
-            raise ValueError('The shebang (%r) is not decodable from utf-8' %
-                             shebang)
+            raise ValueError('The shebang (%r) is not decodable from utf-8' % shebang)
         # If the script is encoded to a custom encoding (use a
         # #coding:xxx cookie), the shebang has to be decodable from
         # the script encoding too.
@@ -256,15 +243,12 @@ def _get_shebang(self, encoding, post_interp=b'', options=None):
                 shebang.decode(encoding)
             except UnicodeDecodeError:  # pragma: no cover
                 raise ValueError('The shebang (%r) is not decodable '
-                                 'from the script encoding (%r)' %
-                                 (shebang, encoding))
+                                 'from the script encoding (%r)' % (shebang, encoding))
         return shebang
 
     def _get_script_text(self, entry):
         return self.script_template % dict(
-            module=entry.prefix,
-            import_name=entry.suffix.split('.')[0],
-            func=entry.suffix)
+            module=entry.prefix, import_name=entry.suffix.split('.')[0], func=entry.suffix)
 
     manifest = _DEFAULT_MANIFEST
 
@@ -274,9 +258,6 @@ def get_manifest(self, exename):
 
     def _write_script(self, names, shebang, script_bytes, filenames, ext):
         use_launcher = self.add_launchers and self._is_nt
-        linesep = os.linesep.encode('utf-8')
-        if not shebang.endswith(linesep):
-            shebang += linesep
         if not use_launcher:
             script_bytes = shebang + script_bytes
         else:  # pragma: no cover
@@ -289,8 +270,7 @@ def _write_script(self, names, shebang, script_bytes, filenames, ext):
                 source_date_epoch = os.environ.get('SOURCE_DATE_EPOCH')
                 if source_date_epoch:
                     date_time = time.gmtime(int(source_date_epoch))[:6]
-                    zinfo = ZipInfo(filename='__main__.py',
-                                    date_time=date_time)
+                    zinfo = ZipInfo(filename='__main__.py', date_time=date_time)
                     zf.writestr(zinfo, script_bytes)
                 else:
                     zf.writestr('__main__.py', script_bytes)
@@ -321,8 +301,7 @@ def _write_script(self, names, shebang, script_bytes, filenames, ext):
                     except Exception:
                         pass  # still in use - ignore error
             else:
-                if self._is_nt and not outname.endswith(
-                        '.' + ext):  # pragma: no cover
+                if self._is_nt and not outname.endswith('.' + ext):  # pragma: no cover
                     outname = '%s.%s' % (outname, ext)
                 if os.path.exists(outname) and not self.clobber:
                     logger.warning('Skipping existing file %s', outname)
@@ -341,9 +320,7 @@ def get_script_filenames(self, name):
         if 'X' in self.variants:
             result.add('%s%s' % (name, self.version_info[0]))
         if 'X.Y' in self.variants:
-            result.add('%s%s%s.%s' %
-                       (name, self.variant_separator, self.version_info[0],
-                        self.version_info[1]))
+            result.add('%s%s%s.%s' % (name, self.variant_separator, self.version_info[0], self.version_info[1]))
         return result
 
     def _make_script(self, entry, filenames, options=None):
@@ -398,8 +375,7 @@ def _copy_script(self, script, filenames):
                 self._fileop.set_executable_mode([outname])
             filenames.append(outname)
         else:
-            logger.info('copying and adjusting %s -> %s', script,
-                        self.target_dir)
+            logger.info('copying and adjusting %s -> %s', script, self.target_dir)
             if not self._fileop.dry_run:
                 encoding, lines = detect_encoding(f.readline)
                 f.seek(0)
@@ -421,8 +397,7 @@ def dry_run(self):
     def dry_run(self, value):
         self._fileop.dry_run = value
 
-    if os.name == 'nt' or (os.name == 'java'
-                           and os._name == 'nt'):  # pragma: no cover
+    if os.name == 'nt' or (os.name == 'java' and os._name == 'nt'):  # pragma: no cover
         # Executable launcher support.
         # Launchers are from https://bitbucket.org/vinay.sajip/simple_launcher/
 
@@ -435,7 +410,7 @@ def _get_launcher(self, kind):
             name = '%s%s%s.exe' % (kind, bits, platform_suffix)
             if name not in WRAPPERS:
                 msg = ('Unable to find resource %s in package %s' %
-                       (name, distlib_package))
+                       (name, DISTLIB_PACKAGE))
                 raise ValueError(msg)
             return WRAPPERS[name]
 
diff --git a/src/pip/_vendor/distlib/util.py b/src/pip/_vendor/distlib/util.py
index ba58858d0fb..0d5bd7a8bf3 100644
--- a/src/pip/_vendor/distlib/util.py
+++ b/src/pip/_vendor/distlib/util.py
@@ -31,11 +31,9 @@
 import time
 
 from . import DistlibException
-from .compat import (string_types, text_type, shutil, raw_input, StringIO,
-                     cache_from_source, urlopen, urljoin, httplib, xmlrpclib,
-                     HTTPHandler, BaseConfigurator, valid_ident,
-                     Container, configparser, URLError, ZipFile, fsdecode,
-                     unquote, urlparse)
+from .compat import (string_types, text_type, shutil, raw_input, StringIO, cache_from_source, urlopen, urljoin, httplib,
+                     xmlrpclib, HTTPHandler, BaseConfigurator, valid_ident, Container, configparser, URLError, ZipFile,
+                     fsdecode, unquote, urlparse)
 
 logger = logging.getLogger(__name__)
 
@@ -88,8 +86,7 @@ def marker_var(remaining):
                 else:
                     m = STRING_CHUNK.match(remaining)
                     if not m:
-                        raise SyntaxError('error in string literal: %s' %
-                                          remaining)
+                        raise SyntaxError('error in string literal: %s' % remaining)
                     parts.append(m.groups()[0])
                     remaining = remaining[m.end():]
             else:
@@ -210,8 +207,7 @@ def get_versions(ver_remaining):
                         ver_remaining = ver_remaining[m.end():]
                         m = VERSION_IDENTIFIER.match(ver_remaining)
                         if not m:
-                            raise SyntaxError('invalid version: %s' %
-                                              ver_remaining)
+                            raise SyntaxError('invalid version: %s' % ver_remaining)
                         v = m.groups()[0]
                         versions.append((op, v))
                         ver_remaining = ver_remaining[m.end():]
@@ -224,8 +220,7 @@ def get_versions(ver_remaining):
                             break
                         m = COMPARE_OP.match(ver_remaining)
                         if not m:
-                            raise SyntaxError('invalid constraint: %s' %
-                                              ver_remaining)
+                            raise SyntaxError('invalid constraint: %s' % ver_remaining)
                     if not versions:
                         versions = None
                 return versions, ver_remaining
@@ -235,8 +230,7 @@ def get_versions(ver_remaining):
             else:
                 i = remaining.find(')', 1)
                 if i < 0:
-                    raise SyntaxError('unterminated parenthesis: %s' %
-                                      remaining)
+                    raise SyntaxError('unterminated parenthesis: %s' % remaining)
                 s = remaining[1:i]
                 remaining = remaining[i + 1:].lstrip()
                 # As a special diversion from PEP 508, allow a version number
@@ -267,14 +261,8 @@ def get_versions(ver_remaining):
     if not versions:
         rs = distname
     else:
-        rs = '%s %s' % (distname, ', '.join(
-            ['%s %s' % con for con in versions]))
-    return Container(name=distname,
-                     extras=extras,
-                     constraints=versions,
-                     marker=mark_expr,
-                     url=uri,
-                     requirement=rs)
+        rs = '%s %s' % (distname, ', '.join(['%s %s' % con for con in versions]))
+    return Container(name=distname, extras=extras, constraints=versions, marker=mark_expr, url=uri, requirement=rs)
 
 
 def get_resources_dests(resources_root, rules):
@@ -524,8 +512,7 @@ def newer(self, source, target):
         second will have the same "age".
         """
         if not os.path.exists(source):
-            raise DistlibException("file '%r' does not exist" %
-                                   os.path.abspath(source))
+            raise DistlibException("file '%r' does not exist" % os.path.abspath(source))
         if not os.path.exists(target):
             return True
 
@@ -601,12 +588,7 @@ def ensure_dir(self, path):
             if self.record:
                 self.dirs_created.add(path)
 
-    def byte_compile(self,
-                     path,
-                     optimize=False,
-                     force=False,
-                     prefix=None,
-                     hashed_invalidation=False):
+    def byte_compile(self, path, optimize=False, force=False, prefix=None, hashed_invalidation=False):
         dpath = cache_from_source(path, not optimize)
         logger.info('Byte-compiling %s to %s', path, dpath)
         if not self.dry_run:
@@ -617,12 +599,11 @@ def byte_compile(self,
                     assert path.startswith(prefix)
                     diagpath = path[len(prefix):]
             compile_kwargs = {}
-            if hashed_invalidation and hasattr(py_compile,
-                                               'PycInvalidationMode'):
-                compile_kwargs[
-                    'invalidation_mode'] = py_compile.PycInvalidationMode.CHECKED_HASH
-            py_compile.compile(path, dpath, diagpath, True,
-                               **compile_kwargs)  # raise error
+            if hashed_invalidation and hasattr(py_compile, 'PycInvalidationMode'):
+                if not isinstance(hashed_invalidation, py_compile.PycInvalidationMode):
+                    hashed_invalidation = py_compile.PycInvalidationMode.CHECKED_HASH
+                compile_kwargs['invalidation_mode'] = hashed_invalidation
+            py_compile.compile(path, dpath, diagpath, True, **compile_kwargs)  # raise error
         self.record_as_written(dpath)
         return dpath
 
@@ -716,16 +697,14 @@ def value(self):
         return resolve(self.prefix, self.suffix)
 
     def __repr__(self):  # pragma: no cover
-        return '<ExportEntry %s = %s:%s %s>' % (self.name, self.prefix,
-                                                self.suffix, self.flags)
+        return '<ExportEntry %s = %s:%s %s>' % (self.name, self.prefix, self.suffix, self.flags)
 
     def __eq__(self, other):
         if not isinstance(other, ExportEntry):
             result = False
         else:
-            result = (self.name == other.name and self.prefix == other.prefix
-                      and self.suffix == other.suffix
-                      and self.flags == other.flags)
+            result = (self.name == other.name and self.prefix == other.prefix and self.suffix == other.suffix and
+                      self.flags == other.flags)
         return result
 
     __hash__ = object.__hash__
@@ -810,7 +789,7 @@ def get_cache_base(suffix=None):
     return os.path.join(result, suffix)
 
 
-def path_to_cache_dir(path):
+def path_to_cache_dir(path, use_abspath=True):
     """
     Convert an absolute path to a directory name for use in a cache.
 
@@ -820,7 +799,7 @@ def path_to_cache_dir(path):
     #. Any occurrence of ``os.sep`` is replaced with ``'--'``.
     #. ``'.cache'`` is appended.
     """
-    d, p = os.path.splitdrive(os.path.abspath(path))
+    d, p = os.path.splitdrive(os.path.abspath(path) if use_abspath else path)
     if d:
         d = d.replace(':', '---')
     p = p.replace(os.sep, '--')
@@ -865,9 +844,8 @@ def is_string_sequence(seq):
     return result
 
 
-PROJECT_NAME_AND_VERSION = re.compile(
-    '([a-z0-9_]+([.-][a-z_][a-z0-9_]*)*)-'
-    '([a-z0-9_.+-]+)', re.I)
+PROJECT_NAME_AND_VERSION = re.compile('([a-z0-9_]+([.-][a-z_][a-z0-9_]*)*)-'
+                                      '([a-z0-9_.+-]+)', re.I)
 PYTHON_VERSION = re.compile(r'-py(\d\.?\d?)')
 
 
@@ -1003,11 +981,11 @@ def __init__(self, base):
             logger.warning('Directory \'%s\' is not private', base)
         self.base = os.path.abspath(os.path.normpath(base))
 
-    def prefix_to_dir(self, prefix):
+    def prefix_to_dir(self, prefix, use_abspath=True):
         """
         Converts a resource prefix to a directory name in the cache.
         """
-        return path_to_cache_dir(prefix)
+        return path_to_cache_dir(prefix, use_abspath=use_abspath)
 
     def clear(self):
         """
@@ -1092,8 +1070,7 @@ def publish(self, event, *args, **kwargs):
                 logger.exception('Exception during event publication')
                 value = None
             result.append(value)
-        logger.debug('publish %s: args = %s, kwargs = %s, result = %s', event,
-                     args, kwargs, result)
+        logger.debug('publish %s: args = %s, kwargs = %s, result = %s', event, args, kwargs, result)
         return result
 
 
@@ -1145,8 +1122,7 @@ def remove(self, pred, succ):
             raise ValueError('%r not a successor of %r' % (succ, pred))
 
     def is_step(self, step):
-        return (step in self._preds or step in self._succs
-                or step in self._nodes)
+        return (step in self._preds or step in self._succs or step in self._nodes)
 
     def get_steps(self, final):
         if not self.is_step(final):
@@ -1242,8 +1218,7 @@ def dot(self):
 # Unarchiving functionality for zip, tar, tgz, tbz, whl
 #
 
-ARCHIVE_EXTENSIONS = ('.tar.gz', '.tar.bz2', '.tar', '.zip', '.tgz', '.tbz',
-                      '.whl')
+ARCHIVE_EXTENSIONS = ('.tar.gz', '.tar.bz2', '.tar', '.zip', '.tgz', '.tbz', '.whl')
 
 
 def unarchive(archive_filename, dest_dir, format=None, check=True):
@@ -1474,8 +1449,7 @@ def _iglob(path_glob):
 
 
 if ssl:
-    from .compat import (HTTPSHandler as BaseHTTPSHandler, match_hostname,
-                         CertificateError)
+    from .compat import (HTTPSHandler as BaseHTTPSHandler, match_hostname, CertificateError)
 
     #
     # HTTPSConnection which verifies certificates/matches domains
@@ -1487,8 +1461,7 @@ class HTTPSConnection(httplib.HTTPSConnection):
 
         # noinspection PyPropertyAccess
         def connect(self):
-            sock = socket.create_connection((self.host, self.port),
-                                            self.timeout)
+            sock = socket.create_connection((self.host, self.port), self.timeout)
             if getattr(self, '_tunnel_host', False):
                 self.sock = sock
                 self._tunnel()
@@ -1543,9 +1516,8 @@ def https_open(self, req):
                 return self.do_open(self._conn_maker, req)
             except URLError as e:
                 if 'certificate verify failed' in str(e.reason):
-                    raise CertificateError(
-                        'Unable to verify server certificate '
-                        'for %s' % req.host)
+                    raise CertificateError('Unable to verify server certificate '
+                                           'for %s' % req.host)
                 else:
                     raise
 
@@ -1561,9 +1533,8 @@ def https_open(self, req):
     class HTTPSOnlyHandler(HTTPSHandler, HTTPHandler):
 
         def http_open(self, req):
-            raise URLError(
-                'Unexpected HTTP request on what should be a secure '
-                'connection: %s' % req)
+            raise URLError('Unexpected HTTP request on what should be a secure '
+                           'connection: %s' % req)
 
 
 #
@@ -1598,8 +1569,7 @@ def make_connection(self, host):
             kwargs['timeout'] = self.timeout
             if not self._connection or host != self._connection[0]:
                 self._extra_headers = eh
-                self._connection = host, httplib.HTTPSConnection(
-                    h, None, **kwargs)
+                self._connection = host, httplib.HTTPSConnection(h, None, **kwargs)
             return self._connection[1]
 
 
@@ -1789,10 +1759,7 @@ def reader(self, stream, context):
         stream.close()
 
     def run_command(self, cmd, **kwargs):
-        p = subprocess.Popen(cmd,
-                             stdout=subprocess.PIPE,
-                             stderr=subprocess.PIPE,
-                             **kwargs)
+        p = subprocess.Popen(cmd, stdout=subprocess.PIPE, stderr=subprocess.PIPE, **kwargs)
         t1 = threading.Thread(target=self.reader, args=(p.stdout, 'stdout'))
         t1.start()
         t2 = threading.Thread(target=self.reader, args=(p.stderr, 'stderr'))
@@ -1847,10 +1814,7 @@ def read(self):
             if 'distutils' in sections:
                 # let's get the list of servers
                 index_servers = config.get('distutils', 'index-servers')
-                _servers = [
-                    server.strip() for server in index_servers.split('\n')
-                    if server.strip() != ''
-                ]
+                _servers = [server.strip() for server in index_servers.split('\n') if server.strip() != '']
                 if _servers == []:
                     # nothing set, let's try to get the default pypi
                     if 'pypi' in sections:
@@ -1861,9 +1825,7 @@ def read(self):
                         result['username'] = config.get(server, 'username')
 
                         # optional params
-                        for key, default in (('repository',
-                                              self.DEFAULT_REPOSITORY),
-                                             ('realm', self.DEFAULT_REALM),
+                        for key, default in (('repository', self.DEFAULT_REPOSITORY), ('realm', self.DEFAULT_REALM),
                                              ('password', None)):
                             if config.has_option(server, key):
                                 result[key] = config.get(server, key)
@@ -1873,11 +1835,9 @@ def read(self):
                         # work around people having "repository" for the "pypi"
                         # section of their config set to the HTTP (rather than
                         # HTTPS) URL
-                        if (server == 'pypi' and repository
-                                in (self.DEFAULT_REPOSITORY, 'pypi')):
+                        if (server == 'pypi' and repository in (self.DEFAULT_REPOSITORY, 'pypi')):
                             result['repository'] = self.DEFAULT_REPOSITORY
-                        elif (result['server'] != repository
-                              and result['repository'] != repository):
+                        elif (result['server'] != repository and result['repository'] != repository):
                             result = {}
             elif 'server-login' in sections:
                 # old format
@@ -2003,8 +1963,7 @@ def get_host_platform():
             from distutils import sysconfig
         except ImportError:
             import sysconfig
-        osname, release, machine = _osx_support.get_platform_osx(
-            sysconfig.get_config_vars(), osname, release, machine)
+        osname, release, machine = _osx_support.get_platform_osx(sysconfig.get_config_vars(), osname, release, machine)
 
     return '%s-%s-%s' % (osname, release, machine)
 
diff --git a/src/pip/_vendor/distlib/version.py b/src/pip/_vendor/distlib/version.py
index 14171ac938d..d70a96ef51e 100644
--- a/src/pip/_vendor/distlib/version.py
+++ b/src/pip/_vendor/distlib/version.py
@@ -619,8 +619,7 @@ def parse(self, s):
     def is_prerelease(self):
         result = False
         for x in self._parts:
-            if (isinstance(x, string_types) and x.startswith('*') and
-                    x < '*final'):
+            if (isinstance(x, string_types) and x.startswith('*') and x < '*final'):
                 result = True
                 break
         return result
diff --git a/src/pip/_vendor/distlib/wheel.py b/src/pip/_vendor/distlib/wheel.py
index 4a5a30e1d8d..62ab10fb3ad 100644
--- a/src/pip/_vendor/distlib/wheel.py
+++ b/src/pip/_vendor/distlib/wheel.py
@@ -25,9 +25,8 @@
 from .compat import sysconfig, ZipFile, fsdecode, text_type, filter
 from .database import InstalledDistribution
 from .metadata import Metadata, WHEEL_METADATA_FILENAME, LEGACY_METADATA_FILENAME
-from .util import (FileOperator, convert_path, CSVReader, CSVWriter, Cache,
-                   cached_property, get_cache_base, read_exports, tempdir,
-                   get_platform)
+from .util import (FileOperator, convert_path, CSVReader, CSVWriter, Cache, cached_property, get_cache_base,
+                   read_exports, tempdir, get_platform)
 from .version import NormalizedVersion, UnsupportedVersionError
 
 logger = logging.getLogger(__name__)
@@ -88,8 +87,7 @@ def _derive_abi():
 \.whl$
 ''', re.IGNORECASE | re.VERBOSE)
 
-NAME_VERSION_RE = re.compile(
-    r'''
+NAME_VERSION_RE = re.compile(r'''
 (?P<nm>[^-]+)
 -(?P<vn>\d+[^-]*)
 (-(?P<bn>\d+[^-]*))?$
@@ -235,8 +233,7 @@ def filename(self):
         arch = '.'.join(self.arch)
         # replace - with _ as a local version separator
         version = self.version.replace('-', '_')
-        return '%s-%s%s-%s-%s-%s.whl' % (self.name, version, buildver, pyver,
-                                         abi, arch)
+        return '%s-%s%s-%s-%s-%s.whl' % (self.name, version, buildver, pyver, abi, arch)
 
     @property
     def exists(self):
@@ -334,8 +331,7 @@ def get_hash(self, data, hash_kind=None):
         try:
             hasher = getattr(hashlib, hash_kind)
         except AttributeError:
-            raise DistlibException('Unsupported hash algorithm: %r' %
-                                   hash_kind)
+            raise DistlibException('Unsupported hash algorithm: %r' % hash_kind)
         result = hasher(data).digest()
         result = base64.urlsafe_b64encode(result).rstrip(b'=').decode('ascii')
         return hash_kind, result
@@ -513,7 +509,7 @@ def install(self, paths, maker, **kwargs):
         installed, and the headers, scripts, data and dist-info metadata are
         not written. If kwarg ``bytecode_hashed_invalidation`` is True, written
         bytecode will try to use file-hash based invalidation (PEP-552) on
-        supported interpreter versions (CPython 2.7+).
+        supported interpreter versions (CPython 3.7+).
 
         The return value is a :class:`InstalledDistribution` instance unless
         ``options.lib_only`` is True, in which case the return value is ``None``.
@@ -522,8 +518,7 @@ def install(self, paths, maker, **kwargs):
         dry_run = maker.dry_run
         warner = kwargs.get('warner')
         lib_only = kwargs.get('lib_only', False)
-        bc_hashed_invalidation = kwargs.get('bytecode_hashed_invalidation',
-                                            False)
+        bc_hashed_invalidation = kwargs.get('bytecode_hashed_invalidation', False)
 
         pathname = os.path.join(self.dirname, self.filename)
         name_ver = '%s-%s' % (self.name, self.version)
@@ -602,8 +597,7 @@ def install(self, paths, maker, **kwargs):
                     if lib_only and u_arcname.startswith((info_pfx, data_pfx)):
                         logger.debug('lib_only: skipping %s', u_arcname)
                         continue
-                    is_script = (u_arcname.startswith(script_pfx)
-                                 and not u_arcname.endswith('.exe'))
+                    is_script = (u_arcname.startswith(script_pfx) and not u_arcname.endswith('.exe'))
 
                     if u_arcname.startswith(data_pfx):
                         _, where, rp = u_arcname.split('/', 2)
@@ -622,8 +616,7 @@ def install(self, paths, maker, **kwargs):
                         # So ... manually preserve permission bits as given in zinfo
                         if os.name == 'posix':
                             # just set the normal permission bits
-                            os.chmod(outfile,
-                                     (zinfo.external_attr >> 16) & 0x1FF)
+                            os.chmod(outfile, (zinfo.external_attr >> 16) & 0x1FF)
                         outfiles.append(outfile)
                         # Double check the digest of the written file
                         if not dry_run and row[1]:
@@ -636,15 +629,12 @@ def install(self, paths, maker, **kwargs):
                                                            '%s' % outfile)
                         if bc and outfile.endswith('.py'):
                             try:
-                                pyc = fileop.byte_compile(
-                                    outfile,
-                                    hashed_invalidation=bc_hashed_invalidation)
+                                pyc = fileop.byte_compile(outfile, hashed_invalidation=bc_hashed_invalidation)
                                 outfiles.append(pyc)
                             except Exception:
                                 # Don't give up if byte-compilation fails,
                                 # but log it and perhaps warn the user
-                                logger.warning('Byte-compilation failed',
-                                               exc_info=True)
+                                logger.warning('Byte-compilation failed', exc_info=True)
                     else:
                         fn = os.path.basename(convert_path(arcname))
                         workname = os.path.join(workdir, fn)
@@ -732,8 +722,7 @@ def install(self, paths, maker, **kwargs):
                         outfiles.append(p)
 
                     # Write RECORD
-                    dist.write_installed_files(outfiles, paths['prefix'],
-                                               dry_run)
+                    dist.write_installed_files(outfiles, paths['prefix'], dry_run)
                 return dist
             except Exception:  # pragma: no cover
                 logger.exception('installation failed.')
@@ -746,8 +735,7 @@ def _get_dylib_cache(self):
         global cache
         if cache is None:
             # Use native string to avoid issues on 2.x: see Python #20140.
-            base = os.path.join(get_cache_base(), str('dylib-cache'),
-                                '%s.%s' % sys.version_info[:2])
+            base = os.path.join(get_cache_base(), str('dylib-cache'), '%s.%s' % sys.version_info[:2])
             cache = Cache(base)
         return cache
 
@@ -764,7 +752,7 @@ def _get_extensions(self):
                     wf = wrapper(bf)
                     extensions = json.load(wf)
                     cache = self._get_dylib_cache()
-                    prefix = cache.prefix_to_dir(pathname)
+                    prefix = cache.prefix_to_dir(self.filename, use_abspath=False)
                     cache_base = os.path.join(cache.base, prefix)
                     if not os.path.isdir(cache_base):
                         os.makedirs(cache_base)
@@ -774,8 +762,7 @@ def _get_extensions(self):
                             extract = True
                         else:
                             file_time = os.stat(dest).st_mtime
-                            file_time = datetime.datetime.fromtimestamp(
-                                file_time)
+                            file_time = datetime.datetime.fromtimestamp(file_time)
                             info = zf.getinfo(relpath)
                             wheel_time = datetime.datetime(*info.date_time)
                             extract = wheel_time > file_time
@@ -924,12 +911,10 @@ def update_version(version, path):
                 else:
                     parts = [int(s) for s in version[i + 1:].split('.')]
                     parts[-1] += 1
-                    updated = '%s+%s' % (version[:i], '.'.join(
-                        str(i) for i in parts))
+                    updated = '%s+%s' % (version[:i], '.'.join(str(i) for i in parts))
             except UnsupportedVersionError:
-                logger.debug(
-                    'Cannot update non-compliant (PEP-440) '
-                    'version %r', version)
+                logger.debug('Cannot update non-compliant (PEP-440) '
+                             'version %r', version)
             if updated:
                 md = Metadata(path=path)
                 md.version = updated
@@ -971,14 +956,11 @@ def update_version(version, path):
                     update_version(current_version, path)
                 # Decide where the new wheel goes.
                 if dest_dir is None:
-                    fd, newpath = tempfile.mkstemp(suffix='.whl',
-                                                   prefix='wheel-update-',
-                                                   dir=workdir)
+                    fd, newpath = tempfile.mkstemp(suffix='.whl', prefix='wheel-update-', dir=workdir)
                     os.close(fd)
                 else:
                     if not os.path.isdir(dest_dir):
-                        raise DistlibException('Not a directory: %r' %
-                                               dest_dir)
+                        raise DistlibException('Not a directory: %r' % dest_dir)
                     newpath = os.path.join(dest_dir, self.filename)
                 archive_paths = list(path_map.items())
                 distinfo = os.path.join(workdir, info_dir)
@@ -1005,11 +987,20 @@ def compatible_tags():
     """
     Return (pyver, abi, arch) tuples compatible with this Python.
     """
-    versions = [VER_SUFFIX]
-    major = VER_SUFFIX[0]
-    for minor in range(sys.version_info[1] - 1, -1, -1):
-        versions.append(''.join([major, str(minor)]))
+    class _Version:
+        def __init__(self, major, minor):
+            self.major = major
+            self.major_minor = (major, minor)
+            self.string = ''.join((str(major), str(minor)))
+
+        def __str__(self):
+            return self.string
+
 
+    versions = [
+        _Version(sys.version_info.major, minor_version)
+        for minor_version in range(sys.version_info.minor, -1, -1)
+    ]
     abis = []
     for suffix in _get_suffixes():
         if suffix.startswith('.abi'):
@@ -1045,35 +1036,45 @@ def compatible_tags():
                 minor -= 1
 
     # Most specific - our Python version, ABI and arch
-    for abi in abis:
-        for arch in arches:
-            result.append((''.join((IMP_PREFIX, versions[0])), abi, arch))
-            # manylinux
-            if abi != 'none' and sys.platform.startswith('linux'):
-                arch = arch.replace('linux_', '')
-                parts = _get_glibc_version()
-                if len(parts) == 2:
-                    if parts >= (2, 5):
-                        result.append((''.join((IMP_PREFIX, versions[0])), abi,
-                                       'manylinux1_%s' % arch))
-                    if parts >= (2, 12):
-                        result.append((''.join((IMP_PREFIX, versions[0])), abi,
-                                       'manylinux2010_%s' % arch))
-                    if parts >= (2, 17):
-                        result.append((''.join((IMP_PREFIX, versions[0])), abi,
-                                       'manylinux2014_%s' % arch))
-                    result.append(
-                        (''.join((IMP_PREFIX, versions[0])), abi,
-                         'manylinux_%s_%s_%s' % (parts[0], parts[1], arch)))
+    for i, version_object in enumerate(versions):
+        version = str(version_object)
+        add_abis = []
+
+        if i == 0:
+            add_abis = abis
+
+        if IMP_PREFIX == 'cp' and version_object.major_minor >= (3, 2):
+            limited_api_abi = 'abi' + str(version_object.major)
+            if limited_api_abi not in add_abis:
+                add_abis.append(limited_api_abi)
+
+        for abi in add_abis:
+            for arch in arches:
+                result.append((''.join((IMP_PREFIX, version)), abi, arch))
+                # manylinux
+                if abi != 'none' and sys.platform.startswith('linux'):
+                    arch = arch.replace('linux_', '')
+                    parts = _get_glibc_version()
+                    if len(parts) == 2:
+                        if parts >= (2, 5):
+                            result.append((''.join((IMP_PREFIX, version)), abi, 'manylinux1_%s' % arch))
+                        if parts >= (2, 12):
+                            result.append((''.join((IMP_PREFIX, version)), abi, 'manylinux2010_%s' % arch))
+                        if parts >= (2, 17):
+                            result.append((''.join((IMP_PREFIX, version)), abi, 'manylinux2014_%s' % arch))
+                        result.append((''.join(
+                            (IMP_PREFIX, version)), abi, 'manylinux_%s_%s_%s' % (parts[0], parts[1], arch)))
 
     # where no ABI / arch dependency, but IMP_PREFIX dependency
-    for i, version in enumerate(versions):
+    for i, version_object in enumerate(versions):
+        version = str(version_object)
         result.append((''.join((IMP_PREFIX, version)), 'none', 'any'))
         if i == 0:
             result.append((''.join((IMP_PREFIX, version[0])), 'none', 'any'))
 
     # no IMP_PREFIX, ABI or arch dependency
-    for i, version in enumerate(versions):
+    for i, version_object in enumerate(versions):
+        version = str(version_object)
         result.append((''.join(('py', version)), 'none', 'any'))
         if i == 0:
             result.append((''.join(('py', version[0])), 'none', 'any'))
diff --git a/src/pip/_vendor/vendor.txt b/src/pip/_vendor/vendor.txt
index 8f9e3773cb3..eff20408e93 100644
--- a/src/pip/_vendor/vendor.txt
+++ b/src/pip/_vendor/vendor.txt
@@ -1,5 +1,5 @@
 CacheControl==0.14.0
-distlib==0.3.8
+distlib==0.3.9
 distro==1.9.0
 msgpack==1.0.8
 packaging==24.1
diff --git a/tools/vendoring/patches/distlib.patch b/tools/vendoring/patches/distlib.patch
deleted file mode 100644
index 962eab1d74f..00000000000
--- a/tools/vendoring/patches/distlib.patch
+++ /dev/null
@@ -1,60 +0,0 @@
-diff --git a/src/pip/_vendor/distlib/scripts.py b/src/pip/_vendor/distlib/scripts.py
-index cfa45d2af..e16292b83 100644
---- a/src/pip/_vendor/distlib/scripts.py
-+++ b/src/pip/_vendor/distlib/scripts.py
-@@ -49,6 +49,24 @@ if __name__ == '__main__':
-     sys.exit(%(func)s())
- '''
-
-+# Pre-fetch the contents of all executable wrapper stubs.
-+# This is to address https://github.com/pypa/pip/issues/12666.
-+# When updating pip, we rename the old pip in place before installing the
-+# new version. If we try to fetch a wrapper *after* that rename, the finder
-+# machinery will be confused as the package is no longer available at the
-+# location where it was imported from. So we load everything into memory in
-+# advance.
-+
-+# Issue 31: don't hardcode an absolute package name, but
-+# determine it relative to the current package
-+distlib_package = __name__.rsplit('.', 1)[0]
-+
-+WRAPPERS = {
-+    r.name: r.bytes
-+    for r in finder(distlib_package).iterator("")
-+    if r.name.endswith(".exe")
-+}
-+
-
- def enquote_executable(executable):
-     if ' ' in executable:
-@@ -164,6 +164,12 @@ class ScriptMaker(object):
-         """
-         if os.name != 'posix':
-             simple_shebang = True
-+        elif getattr(sys, "cross_compiling", False):
-+            # In a cross-compiling environment, the shebang will likely be a
-+            # script; this *must* be invoked with the "safe" version of the
-+            # shebang, or else using os.exec() to run the entry script will
-+            # fail, raising "OSError 8 [Errno 8] Exec format error".
-+            simple_shebang = False
-         else:
-             # Add 3 for '#!' prefix and newline suffix.
-             shebang_length = len(executable) + len(post_interp) + 3
-@@ -409,15 +427,11 @@ class ScriptMaker(object):
-                 bits = '32'
-             platform_suffix = '-arm' if get_platform() == 'win-arm64' else ''
-             name = '%s%s%s.exe' % (kind, bits, platform_suffix)
--            # Issue 31: don't hardcode an absolute package name, but
--            # determine it relative to the current package
--            distlib_package = __name__.rsplit('.', 1)[0]
--            resource = finder(distlib_package).find(name)
--            if not resource:
-+            if name not in WRAPPERS:
-                 msg = ('Unable to find resource %s in package %s' %
-                        (name, distlib_package))
-                 raise ValueError(msg)
--            return resource.bytes
-+            return WRAPPERS[name]
- 
-     # Public API follows
-