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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 compute(mechanism, subsystem, purviews, cause_purviews, effect_purviews):
 """Compute a |Concept| for a mechanism, in this |Subsystem| with the provided purviews. """

        concept = subsystem.concept(mechanism,
                                    purviews=purviews,
                                    cause_purviews=cause_purviews,
                                    effect_purviews=effect_purviews)
        # Don't serialize the subsystem.
        # This is replaced on the other side of the queue, and ensures
        # that all concepts in the CES reference the same subsystem.
        concept.subsystem = None
        return concept