diff --git a/stdlib/2and3/difflib.pyi b/stdlib/2and3/difflib.pyi
index 407d563ef..5b285e070 100644
--- a/stdlib/2and3/difflib.pyi
+++ b/stdlib/2and3/difflib.pyi
@@ -42,7 +42,7 @@ def get_close_matches(word: Sequence[_T], possibilities: Iterable[Sequence[_T]],
                       n: int = ..., cutoff: float = ...) -> List[Sequence[_T]]: ...
 
 class Differ:
-    def __init__(self, linejunk: _JunkCallback = ..., charjunk: _JunkCallback = ...) -> None: ...
+    def __init__(self, linejunk: Optional[_JunkCallback] = ..., charjunk: Optional[_JunkCallback] = ...) -> None: ...
     def compare(self, a: Sequence[_StrType], b: Sequence[_StrType]) -> Iterator[_StrType]: ...
 
 def IS_LINE_JUNK(line: _StrType, pat: Any = ...) -> bool: ...  # pat is undocumented
@@ -54,14 +54,14 @@ def context_diff(a: Sequence[_StrType], b: Sequence[_StrType], fromfile: _StrTyp
                  tofile: _StrType = ..., fromfiledate: _StrType = ..., tofiledate: _StrType = ...,
                  n: int = ..., lineterm: _StrType = ...) -> Iterator[_StrType]: ...
 def ndiff(a: Sequence[_StrType], b: Sequence[_StrType],
-          linejunk: _JunkCallback = ...,
-          charjunk: _JunkCallback = ...
+          linejunk: Optional[_JunkCallback] = ...,
+          charjunk: Optional[_JunkCallback] = ...
           ) -> Iterator[_StrType]: ...
 
 class HtmlDiff(object):
-    def __init__(self, tabsize: int = ..., wrapcolumn: int = ...,
-                 linejunk: _JunkCallback = ...,
-                 charjunk: _JunkCallback = ...
+    def __init__(self, tabsize: int = ..., wrapcolumn: Optional[int] = ...,
+                 linejunk: Optional[_JunkCallback] = ...,
+                 charjunk: Optional[_JunkCallback] = ...
                  ) -> None: ...
     if sys.version_info >= (3, 5):
         def make_file(self, fromlines: Sequence[_StrType], tolines: Sequence[_StrType],
diff --git a/tests/stubtest_whitelists/py3_common.txt b/tests/stubtest_whitelists/py3_common.txt
index ebbab9c33..51ee9ff62 100644
--- a/tests/stubtest_whitelists/py3_common.txt
+++ b/tests/stubtest_whitelists/py3_common.txt
@@ -261,10 +261,7 @@ curses.textpad.Textbox.edit
 dbm.error
 dbm.ndbm
 decimal.DecimalException.handle
-difflib.Differ.__init__
-difflib.HtmlDiff.__init__
 difflib.SequenceMatcher.__init__
-difflib.ndiff
 dis.dis
 distutils.archive_util.make_archive
 distutils.archive_util.make_tarball