def test_yieldsMachine(self):
        """
        When given a L{twisted.python.modules.PythonAttribute} that refers
        directly to a L{MethodicalMachine}, L{findMachinesViaWrapper}
        yields that machine and its FQPN.
        """
        source = """\
        from automat import MethodicalMachine

        rootMachine = MethodicalMachine()
        """

        moduleDict = self.makeModuleAsDict(source, self.pathDir, 'root.py')
        rootMachine = moduleDict['root.rootMachine']
        self.assertIn(('root.rootMachine', rootMachine.load()),
                      list(self.findMachinesViaWrapper(rootMachine)))

        When given a L{twisted.python.modules.PythonAttribute} that refers
        directly to a L{MethodicalMachine}, L{findMachinesViaWrapper}
        yields that machine and its FQPN.
        
stackoverflow/venv/lib/python3.6/site-packages/automat/_test/test_discover.py