def test_groups(self):
        """
        CompleteGroups produces zsh shell-code that completes system group
        names.
        """
        c = usage.CompleteGroups()
        out = c._shellCode('some-option', usage._ZSH)
        self.assertEqual(out, ':group:_groups')

        c = usage.CompleteGroups(descr='some action', repeat=True)
        out = c._shellCode('some-option', usage._ZSH)
        self.assertEqual(out, '*:some action:_groups')

        CompleteGroups produces zsh shell-code that completes system group
        names.
        
stackoverflow/venv/lib/python3.6/site-packages/twisted/test/test_usage.py