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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 gate to memory."""

        memory.seek(0)
        memory.write(struct.pack("<5I",
                                 # sim_length
                                 self._simulator.length,
                                 # input_a_key
                                 self._inputs["a"].routing_key
                                 if self._inputs["a"] is not None
                                 else 0xFFFFFFFF,
                                 # input_b_key
                                 self._inputs["b"].routing_key
                                 if self._inputs["b"] is not None
                                 else 0xFFFFFFFF,
                                 # output_key
                                 self.output.routing_key,
                                 # lut
                                 self._lookup_table))