code: def query_nds2(cls, name, host=None, port=None, connection=None,
                     type=None):
          
          return ChannelList.query_nds2([name], host=host, port=port,
                                        connection=connection, type=type,
                                        unique=True)[0]
docs: Query an NDS server for channel information
  
          Parameters
          ----------
          name : `str`
              name of requested channel
          host : `str`, optional
              name of NDS2 server.
          port : `int`, optional
              port number for NDS2 connection
          connection : `nds2.connection`
              open connection to use for query
          type : `str`, `int`
              NDS2 channel type with which to restrict query
  
          Returns
          -------
          channel : `Channel`
              channel with metadata retrieved from NDS2 server
  
          Raises
          ------
          ValueError
              if multiple channels are found for a given name
  
          Notes
          -----
          .. warning::
  
             A `host` is required if an open `connection` is not given