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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 _Open(self, hostname, port):
 """Opens the RPC communication channel for clients. Args: hostname (str):
 hostname or IP address to connect to for requests. port (int):
 port to connect to for requests. Returns: bool: True if the communication channel was successfully opened. """

    try:
      self._xmlrpc_server = SimpleXMLRPCServer.SimpleXMLRPCServer(
          (hostname, port), logRequests=False, allow_none=True)
    except SocketServer.socket.error as exception:
      logger.warning((
          'Unable to bind a RPC server on {0:s}:{1:d} with error: '
          '{2!s}').format(hostname, port, exception))
      return False

    self._xmlrpc_server.register_function(
        self._callback, self._RPC_FUNCTION_NAME)
    return True