diff -r 346af7687c6f -r 89a2afe31e82 mercurial/diffutil.py
--- a/mercurial/diffutil.py	Fri Nov 27 17:00:00 2020 -0500
+++ b/mercurial/diffutil.py	Fri Nov 27 17:03:29 2020 -0500
@@ -43,14 +43,14 @@
     formatchanging=False,
     configprefix=b'',
 ):
-    '''return diffopts with only opted-in features parsed
+    """return diffopts with only opted-in features parsed
 
     Features:
     - git: git-style diffs
     - whitespace: whitespace options like ignoreblanklines and ignorews
     - formatchanging: options that will likely break or cause correctness issues
       with most diff parsers
-    '''
+    """
 
     def get(key, name=None, getter=ui.configbool, forceplain=None):
         if opts: