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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 requires(self, from_, if_=None, **data):
 """ Decorates a method that may be called if the given state is currently active. Registers a transition internally, but does not change the state. :param from_: Required state to allow this call (can be a state group) :param if_: Validator(s) that, given the object, must all return True for the call to proceed :param data: Additional metadata, stored on the `StateTransition` object as a :attr:`data` attribute """

        return self.transition(from_, None, if_, **data)