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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 set_optimizer(self, optimizer):
 """ Registers an optimizer with the kvstore. When using a single machine, this function updates the local optimizer. If using multiple machines and this operation is invoked from a worker node, it will serialized the optimizer with pickle and send it to all servers. The function returns after all servers have been updated. Parameters optimizer : Optimizer The new optimizer for the store Examples -------- array([[-0.01, -0.01], [-0.01, -0.01]], dtype=float32) """

        is_worker = ctypes.c_int()
        check_call(_LIB.MXKVStoreIsWorkerNode(ctypes.byref(is_worker)))

        # pylint: disable=invalid-name
        if 'dist' in self.type and is_worker.value: # pylint: disable=unsupported-membership-test
            # send the optimizer to server
            try:
                # use ASCII protocol 0, might be slower, but not a big ideal
                optim_str = py_str(pickle.dumps(optimizer, 0))
            except:
                raise
            cmd = _get_kvstore_server_command_type('kController')
            self._send_command_to_servers(cmd, optim_str)
            if optimizer.multi_precision:
                cmd = _get_kvstore_server_command_type('kSetMultiPrecision')
                self._send_command_to_servers(cmd, '')
        else:
            self._set_updater(opt.get_updater(optimizer))