diff --git a/Lib/unittest/mock.py b/Lib/unittest/mock.py
index a3d8b6eab41a986..37ea5c7e45c8bcd 100644
--- a/Lib/unittest/mock.py
+++ b/Lib/unittest/mock.py
@@ -2748,7 +2748,7 @@ def _must_skip(spec, entry, is_type):
             continue
         if isinstance(result, (staticmethod, classmethod)):
             return False
-        elif isinstance(getattr(result, '__get__', None), MethodWrapperTypes):
+        elif isinstance(result, FunctionTypes):
             # Normal method => skip if looked up on type
             # (if looked up on instance, self is already skipped)
             return is_type
@@ -2778,10 +2778,6 @@ def __init__(self, spec, spec_set=False, parent=None,
     type(ANY.__eq__),
 )
 
-MethodWrapperTypes = (
-    type(ANY.__eq__.__get__),
-)
-
 
 file_spec = None
 
diff --git a/Misc/NEWS.d/next/Library/2020-01-29-14-58-27.bpo-39485.Zy3ot6.rst b/Misc/NEWS.d/next/Library/2020-01-29-14-58-27.bpo-39485.Zy3ot6.rst
new file mode 100644
index 000000000000000..f62c31fc686ad8f
--- /dev/null
+++ b/Misc/NEWS.d/next/Library/2020-01-29-14-58-27.bpo-39485.Zy3ot6.rst
@@ -0,0 +1,3 @@
+Fix a bug in :func:`unittest.mock.create_autospec` that would complain about
+the wrong number of arguments for custom descriptors defined in an extension
+module returning functions.