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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:
 """Simulate a set of phase gates on the xmon architecture. Args: phase_map: A map from a tuple of indices to a value, one for each phase gate being simulated. If the tuple key has one index, then this is a Z phase gate on the index-th qubit with a rotation angle of pi times the value of the map. If the tuple key has two indices, then this is a |11> phasing gate, acting on the qubits at the two indices, and a rotation angle of pi times the value of the map. """

        self._pool.map(_clear_scratch, self._shard_num_args())
        # Iterate over the map of phase data.
        for indices, half_turns in phase_map.items():
            args = self._shard_num_args(
                {'indices': indices, 'half_turns': half_turns})
            if len(indices) == 1:
                self._pool.map(_single_qubit_accumulate_into_scratch, args)
            elif len(indices) == 2:
                self._pool.map(_two_qubit_accumulate_into_scratch, args)
        # Exponentiate the phases and add them into the state.
        self._pool.map(_apply_scratch_as_phase, self._shard_num_args())