Unable to mock old-style classes

import unittest
import mocker

class OldStyle: pass
class NewStyle(object): pass

class TestCase(mocker.MockerTestCase):

    def test_new_style(self):
        mockedclass = self.mocker.replace(NewStyle)
        self.expect(mockedclass())
        self.mocker.replay()
        obj = NewStyle()

    def test_old_style(self):
        mockedclass = self.mocker.replace(OldStyle)
        self.expect(mockedclass())
        self.mocker.replay()
        obj = OldStyle()

if __name__ == '__main__':
    unittest.main()
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