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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 a RPC communication channel to the server. 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 established. """

    server_url = 'http://{0:s}:{1:d}'.format(hostname, port)

    try:
      self._xmlrpc_proxy = xmlrpclib.ServerProxy(
          server_url, allow_none=True)
    except SocketServer.socket.error as exception:
      logger.warning((
          'Unable to connect to RPC server on {0:s}:{1:d} with error: '
          '{2!s}').format(hostname, port, exception))
      return False

    return True