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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 outputs_of(self, partition_index):
 """The outputs of the partition at ``partition_index``. Note that this returns a tuple of element indices, since coarse- grained blackboxes may have multiple outputs. """

        partition = self.partition[partition_index]
        outputs = set(partition).intersection(self.output_indices)
        return tuple(sorted(outputs))