Based on my research, I can now generate the correct patch for the Django slugify issue. The fix requires changing `.strip()` to `.strip('-_')` and updating the docstring to reflect this behavior change.

--- a/django/utils/text.py
+++ b/django/utils/text.py
@@ -393,12 +393,12 @@ def slugify(value, allow_unicode=False):
     """
     Convert to ASCII if 'allow_unicode' is False. Convert spaces or repeated
     dashes to single dashes. Remove characters that aren't alphanumerics,
-    underscores, or hyphens. Convert to lowercase. Also strip leading and
-    trailing whitespace.
+    underscores, or hyphens. Convert to lowercase. Also strip leading and
+    trailing whitespace, dashes, and underscores.
     """
     value = str(value)
     if allow_unicode:
         value = unicodedata.normalize('NFKC', value)
     else:
         value = unicodedata.normalize('NFKD', value).encode('ascii', 'ignore').decode('ascii')
     value = re.sub(r'[^\w\s-]', '', value.lower())
-    return re.sub(r'[-\s]+', '-', value).strip()
+    return re.sub(r'[-\s]+', '-', value).strip('-_')