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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 all_blackboxes(indices):
 """Generator over all possible blackboxings of these indices. Args: indices (tuple[int]):
 Nodes to blackbox. Yields: Blackbox: The next |Blackbox| of ``indices``. """

    for partition in all_partitions(indices):
        # TODO? don't consider the empty set here
        # (pass `nonempty=True` to `powerset`)
        for output_indices in utils.powerset(indices):
            blackbox = Blackbox(partition, output_indices)
            try:  # Ensure every box has at least one output
                validate.blackbox(blackbox)
            except ValueError:
                continue
            yield blackbox