Address comments in ead.py

* Remove assignments for private methods retrieving 'controlaccess', 'archdesc',
  and 'did' elements

transmogrifier/sources/xml/ead.py

@@ -291,8 +291,7 @@ def get_citation(cls, source_record: Tag) -> str | None:
     @classmethod
     def get_content_type(cls, source_record: Tag) -> list[str] | None:
         content_types = ["Archival materials"]
-        control_access_elements = cls._get_control_access(source_record)
-        for control_access_element in control_access_elements:
+        for control_access_element in cls._get_control_access(source_record):
             _content_types = [
                 content_type
                 for content_type_element in control_access_element.find_all("genreform")
@@ -371,10 +370,11 @@ def _get_contributor_identifier_url(cls, name_element: Tag) -> list | None:
     @classmethod
     def get_dates(cls, source_record: Tag) -> list[timdex.Date] | None:
         dates = []
-        collection_description_did = cls._get_collection_description_did(source_record)
         source_record_id = cls.get_source_record_id(source_record)
         dates.extend(
-            cls._parse_date_elements(collection_description_did, source_record_id)
+            cls._parse_date_elements(
+                cls._get_collection_description_did(source_record), source_record_id
+            )
         )
         return dates or None
 
@@ -475,8 +475,7 @@ def get_languages(cls, source_record: Tag) -> list[str] | None:
     @classmethod
     def get_locations(cls, source_record: Tag) -> list[timdex.Location] | None:
         locations = []
-        control_access_elements = cls._get_control_access(source_record)
-        for control_access_element in control_access_elements:
+        for control_access_element in cls._get_control_access(source_record):
             locations.extend(
                 [
                     timdex.Location(value=location)