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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 _init_scratch(self):
 """Initializes a scratch pad equal in size to the wavefunction."""

        scratch = np.zeros((self._num_shards, self._shard_size),
                           dtype=np.complex64)
        scratch_handle = mem_manager.SharedMemManager.create_array(
            scratch.view(dtype=np.float32))
        self._shared_mem_dict['scratch_handle'] = scratch_handle