def _change_volume(self, increase):
sign = "<STR_LIT:+>" if increase else "<STR_LIT:->"<EOL>delta = "<STR_LIT>" % (self.volume_tick, sign)<EOL>self._run(["<STR_LIT>", "<STR_LIT>", "<STR_LIT>", "<STR_LIT>", delta])<EOL>
Change volume using amixer