test_methodical.py

        class Mechanism(object):
            m = MethodicalMachine()
            def __init__(self):
                self.value = 1
            @m.state(serialized="first-state")
            def first(self):
                "First state."
            @m.state(serialized="second-state")
            def second(self):
                "Second state."

            _state = m.state.descriptor()