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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 make_rpc_call(self, rpc_command):
 """ Allow a user to query a device directly using XML-requests. :param rpc_command: (str) rpc command such as: <Get><Operational><LLDP><NodeTable></NodeTable></LLDP></Operational></Get> """

        # ~~~ hack: ~~~
        if not self.is_alive():
            self.close()  # force close for safety
            self.open()  # reopen
        # ~~~ end hack ~~~
        result = self._execute_rpc(rpc_command)
        return ET.tostring(result)