def _change_channel_group(step, params):
 radio = params['fig_selection'].radio
 idx = radio._active_idx
 if (step < 0):
  if (idx < (len(radio.labels) - 1)):
   _set_radio_button((idx + 1), params)
 elif (idx > 0):
  _set_radio_button((idx - 1), params)
 return

def _change_channel_group ( step , params ) : radio = params [ 'fig_selection' ] . radio idx = radio . _active_idx if ( step < 0 ) : if ( idx < ( len ( radio . labels ) - 1 ) ) : _set_radio_button ( ( idx + 1 ) , params ) elif ( idx > 0 ) : _set_radio_button ( ( idx - 1 ) , params ) return
deal with change of channel group .