code: def _x_open(self):
          
          if self.is_open:
              return
  
          args = AMQPWriter()
          args.write_shortstr('')  # out_of_band: deprecated
          self._send_method((20, 10), args)
          return self.wait(allowed_methods=[
              (20, 11),  # Channel.open_ok
          ])
docs: Open a channel for use
  
          This method opens a virtual connection (a channel).
  
          RULE:
  
              This method MUST NOT be called when the channel is already
              open.
  
          PARAMETERS:
              out_of_band: shortstr (DEPRECATED)
  
                  out-of-band settings
  
                  Configures out-of-band transfers on this channel.  The
                  syntax and meaning of this field will be formally
                  defined at a later date.