code: def digital_channel_air(self, opt1='?', opt2='?'):
          
          if opt1 == '?':
              parameter = '?'
          elif opt2 == '?':
              parameter = str(opt1).rjust(4, "0")
          else:
              parameter = '{:02d}{:02d}'.format(opt1, opt2)
          return self._send_command('digital_channel_air', parameter)
docs: Description:
  
              Change Channel (Digital)
              Pass Channels "XX.YY" as TV.digital_channel_air(XX, YY)
  
          Arguments:
              opt1: integer
                  1-99: Major Channel
              opt2: integer (optional)
                  1-99: Minor Channel