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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 evaluate_partition(self, direction, mechanism, purview, partition, repertoire=None):
 """Return the |small_phi| of a mechanism over a purview for the given partition. Args: direction (Direction):
 |CAUSE| or |EFFECT|. mechanism (tuple[int]):
 The nodes in the mechanism. purview (tuple[int]):
 The nodes in the purview. partition (Bipartition):
 The partition to evaluate. Keyword Args: repertoire (np.array):
 The unpartitioned repertoire. If not supplied, it will be computed. Returns: tuple[int, np.ndarray]: The distance between the unpartitioned and partitioned repertoires, and the partitioned repertoire. """

        if repertoire is None:
            repertoire = self.repertoire(direction, mechanism, purview)

        partitioned_repertoire = self.partitioned_repertoire(direction,
                                                             partition)

        phi = repertoire_distance(
            direction, repertoire, partitioned_repertoire)

        return (phi, partitioned_repertoire)