How do I patch a classmethod?

output

 python -m unittest patch_classmethod
E
======================================================================
ERROR: test_usesCreate (patch_classmethod.someFuncTest)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "patch_classmethod.py", line 27, in test_usesCreate
    someFunc('hey')
  File "patch_classmethod.py", line 11, in someFunc
    return Foo.create(arg)
TypeError: unbound method create() must be called with Foo instance as first argument (got str instance instead)

----------------------------------------------------------------------
Ran 1 test in 0.001s

FAILED (errors=1)

patch_classmethod.py

class Foo(object):

    @classmethod
    def create(self, arg):
        foo = Foo()
        foo.value = arg
        return foo


def someFunc(arg):
    return Foo.create(arg)



from unittest import TestCase
from mock import patch


class someFuncTest(TestCase):

    
    def test_usesCreate(self):
        """
        someFunc should use Foo.create to create the foo instance.
        """
        with patch.object(Foo, 'create', autospec=Foo.create):
            someFunc('hey')
            Foo.create.assert_called_once_with('hey')