'Get the volume.
Integer in range [0..100] or :class:`None` if unknown.
The volume scale is linear.'

def get_volume(self):

    if (self._mixer is None):
        return None
    with _mixer_error_handling(self._mixer):
        volume = self._mixer.get_volume().get()
        ((volume is None) or validation.check_integer(volume, min=0, max=100))
        return volume
    return None
