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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 _write_config(self, memory):
 """Write the configuration for this stimulus to memory."""

        memory.seek(0)
        memory.write(struct.pack("<II",
                                 # sim_length
                                 self._simulator.length,
                                 # output_key
                                 self.output.routing_key))

        # NB: memory.write will automatically truncate any excess stimulus
        memory.write(bitarray(
            self.stimulus.ljust(self._simulator.length, "0"),
            endian="little").tobytes())