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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def state(self, initial=False, terminal=False, serialized=None):
 """ Declare a state, possibly an initial state or a terminal state. This is a decorator for methods, but it will modify the method so as not to be callable any more. :param bool initial: is this state the initial state? Only one state on this :class:`automat.MethodicalMachine` may be an initial state; more than one is an error. :param bool terminal: Is this state a terminal state? i.e. a state that the machine can end up in? (This is purely informational at this point.) :param Hashable serialized: a serializable value to be used to represent this state to external systems. This value should be hashable; :py:func:`unicode` is a good type to use. """

        def decorator(stateMethod):
            state = MethodicalState(machine=self,
                                    method=stateMethod,
                                    serialized=serialized)
            if initial:
                self._automaton.initialState = state
            return state
        return decorator