def _change_volume(self, step=None, value=None):
if step is not None:
volume = sound.get_volume() + step
elif value is not None:
volume = value
volume = min(max(0, volume), _VOLUME_MAX)
sound.set_volume(volume)
sound.set_muted(volume == 0)
def _change_volume(self, step=None, value=None):
if step is not None:
volume = sound.get_volume() + step
elif value is not None:
volume = value
volume = min(max(0, volume), _VOLUME_MAX)
sound.set_volume(volume)
sound.set_muted(volume == 0)