Possible incompatibility with Sphinx 3.1.0 #105

WARNING: autodoc: failed to import method '__call__' from module 'keyword'; the following exception was raised:
Traceback (most recent call last):
  File "c:\...\sphinx\util\inspect.py", line 323, in safe_getattr
    return getattr(obj, name, *defargs)
AttributeError: module 'keyword' has no attribute '__call__'

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
  File "c:\...\sphinx\ext\autodoc\importer.py", line 71, in import_object
    obj = attrgetter(obj, attrname)
  File "c:\...\sphinx\ext\autodoc\__init__.py", line 246, in get_attr
    return autodoc_attrgetter(self.env.app, obj, name, *defargs)
  File "c:\...\sphinx\ext\autodoc\__init__.py", line 2059, in autodoc_attrgetter
    return safe_getattr(obj, name, *defargs)
  File "c:\...\sphinx\util\inspect.py", line 339, in safe_getattr
    raise AttributeError(name)
AttributeError: __call__