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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 _send_command_to_servers(self, head, body):
 """Sends a command to all server nodes. Sending command to a server node will cause that server node to invoke ``KVStoreServer.controller`` to execute the command. This function returns after the command has been executed on all server nodes. Parameters head : int the head of the command. body : str the body of the command. """

        check_call(_LIB.MXKVStoreSendCommmandToServers(
            self.handle, mx_uint(head), c_str(body)))