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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 order(self, mechanism, purview):
 """Order the mechanism and purview in time. If the direction is ``CAUSE``, then the purview is at |t-1| and the mechanism is at time |t|. If the direction is ``EFFECT``, then the mechanism is at time |t| and the purview is at |t+1|. """

        if self is Direction.CAUSE:
            return purview, mechanism
        elif self is Direction.EFFECT:
            return mechanism, purview

        from . import validate
        return validate.direction(self)