webassets.exceptions.FilterError [SCSS] subprocess returned a non-success result code

[smurf-U]

assets_frontend_css = [
    'website/src/scss/color.scss',
    'website/src/scss/common.scss',
]
assets_bundles = {

    'assets_frontend_css': Bundle(
        *assets_frontend_css,
        output='gen/assets_frontend.css',
        filters='scss,cssmin', extra={'rel': 'stylesheet/css'}),
}
app = Flask(__name__)
assets = Environment(app)
assets.register(assets_bundles)

color.scss

$primary-color : #48b1bf;
$secondary-color: #646464;

common.scss

body{
    background: $primary-color;
    color: $secondary-color;
}

Error give as below,

webassets.exceptions.FilterError
webassets.exceptions.FilterError: scss: subprocess returned a non-success result code: 64, stdout=b'Could not find an option named "line-comments".\n\nUsage: sass <input.scss> [output.css]\n       sass <input.scss>:<output.css> <input/>:<output/> <dir/>\n\n\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81 Input and Output \xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\n    --[no-]stdin               Read the stylesheet from stdin.\n    --[no-]indented            Use the indented syntax for input from stdin.\n-I, --load-path=<PATH>         A path to use when resolving imports.\n                               May be passed multiple times.\n\n-s, --style=<NAME>             Output style.\n                               [expanded (default), compressed]\n\n    --[no-]charset             Emit a @charset or BOM for CSS with non-ASCII characters.\n                               (defaults to on)\n\n    --[no-]error-css           When an error occurs, emit a stylesheet describing it.\n                               Defaults to true when compiling to a file.\n\n    --update                   Only compile out-of-date stylesheets.\n\n\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81 Source Maps \xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\n    --[no-]source-map          Whether to generate source maps.\n                               (defaults to on)\n\n    --source-map-urls          How to link from source maps to source files.\n                               [relative (default), absolute]\n\n    --[no-]embed-sources       Embed source file contents in source maps.\n    --[no-]embed-source-map    Embed source map contents in CSS.\n\n\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81 Other \xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\n    --watch                    Watch stylesheets and recompile when they change.\n    --[no-]poll                Manually check for changes rather than using a native watcher.\n                               Only valid with --watch.\n\n    --[no-]stop-on-error       Don\'t compile more files once an error is encountered.\n-i, --interactive              Run an interactive SassScript shell.\n-c, --[no-]color               Whether to use terminal colors for messages.\n    --[no-]unicode             Whether to use Unicode characters for messages.\n-q, --[no-]quiet               Don\'t print warnings.\n    --[no-]trace               Print full Dart stack traces for exceptions.\n-h, --help                     Print this usage information.\n    --version                  Print the version of Dart Sass.\n', stderr=b''

Traceback (most recent call last)
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/app.py", line 2463, in __call__
return self.wsgi_app(environ, start_response)
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/app.py", line 2449, in wsgi_app
response = self.handle_exception(e)
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/app.py", line 1866, in handle_exception
reraise(exc_type, exc_value, tb)
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/_compat.py", line 39, in reraise
raise value
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/app.py", line 2446, in wsgi_app
response = self.full_dispatch_request()
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/app.py", line 1951, in full_dispatch_request
rv = self.handle_user_exception(e)
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/app.py", line 1820, in handle_user_exception
reraise(exc_type, exc_value, tb)
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/_compat.py", line 39, in reraise
raise value
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/app.py", line 1949, in full_dispatch_request
rv = self.dispatch_request()
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/app.py", line 1935, in dispatch_request
return self.view_functions[rule.endpoint](**req.view_args)
File "/home/kaushal/flask_workspace/portfolio/app/website/controllers.py", line 32, in index
return render_template("index.html")
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/templating.py", line 140, in render_template
ctx.app,
File "/home/kaushal/.local/lib/python3.6/site-packages/flask/templating.py", line 120, in _render
rv = template.render(context)
File "/home/kaushal/.local/lib/python3.6/site-packages/jinja2/asyncsupport.py", line 76, in render
return original_render(self, *args, **kwargs)
File "/home/kaushal/.local/lib/python3.6/site-packages/jinja2/environment.py", line 1008, in render
return self.environment.handle_exception(exc_info, True)
File "/home/kaushal/.local/lib/python3.6/site-packages/jinja2/environment.py", line 780, in handle_exception
reraise(exc_type, exc_value, tb)
File "/home/kaushal/.local/lib/python3.6/site-packages/jinja2/_compat.py", line 37, in reraise
raise value.with_traceback(tb)
File "/home/kaushal/flask_workspace/portfolio/app/website/templates/index.html", line 10, in top-level template code
{% assets "assets_frontend_css" %}
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/ext/jinja2.py", line 186, in _render_assets
urls = bundle.urls()
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/bundle.py", line 806, in urls
urls.extend(bundle._urls(new_ctx, extra_filters, *args, **kwargs))
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/bundle.py", line 765, in _urls
*args, **kwargs)
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/bundle.py", line 619, in _build
force, disable_cache=disable_cache, extra_filters=extra_filters)
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/bundle.py", line 543, in _merge_and_apply
kwargs=item_data)
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/merge.py", line 276, in apply
return self._wrap_cache(key, func)
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/merge.py", line 218, in _wrap_cache
content = func().getvalue()
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/merge.py", line 251, in func
getattr(filter, type)(data, out, **kwargs_final)
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/filter/sass.py", line 196, in input
self._apply_sass(_in, out, os.path.dirname(source_path))
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/filter/sass.py", line 190, in _apply_sass
return self.subprocess(args, out, _in, cwd=child_cwd)
File "/home/kaushal/.local/lib/python3.6/site-packages/webassets/filter/__init__.py", line 527, in subprocess
proc.returncode, stdout, stderr))
webassets.exceptions.FilterError: scss: subprocess returned a non-success result code: 64, stdout=b'Could not find an option named "line-comments".\n\nUsage: sass <input.scss> [output.css]\n sass <input.scss>:<output.css> <input/>:<output/> <dir/>\n\n\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81 Input and Output \xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\n --[no-]stdin Read the stylesheet from stdin.\n --[no-]indented Use the indented syntax for input from stdin.\n-I, --load-path=<PATH> A path to use when resolving imports.\n May be passed multiple times.\n\n-s, --style=<NAME> Output style.\n [expanded (default), compressed]\n\n --[no-]charset Emit a @charset or BOM for CSS with non-ASCII characters.\n (defaults to on)\n\n --[no-]error-css When an error occurs, emit a stylesheet describing it.\n Defaults to true when compiling to a file.\n\n --update Only compile out-of-date stylesheets.\n\n\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81 Source Maps \xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\n --[no-]source-map Whether to generate source maps.\n (defaults to on)\n\n --source-map-urls How to link from source maps to source files.\n [relative (default), absolute]\n\n --[no-]embed-sources Embed source file contents in source maps.\n --[no-]embed-source-map Embed source map contents in CSS.\n\n\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81 Other \xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\xe2\x94\x81\n --watch Watch stylesheets and recompile when they change.\n --[no-]poll Manually check for changes rather than using a native watcher.\n Only valid with --watch.\n\n --[no-]stop-on-error Don\'t compile more files once an error is encountered.\n-i, --interactive Run an interactive SassScript shell.\n-c, --[no-]color Whether to use terminal colors for messages.\n --[no-]unicode Whether to use Unicode characters for messages.\n-q, --[no-]quiet Don\'t print warnings.\n --[no-]trace Print full Dart stack traces for exceptions.\n-h, --help Print this usage information.\n --version Print the version of Dart Sass.\n', stderr=b''
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