def cmd_currentsong(self, conn):
        if self.current_index != -1:  # -1 means stopped.
            track = self.playlist[self.current_index]
            yield self._item_info(track)
Set the where clause for the relation query.
dataset/ETHPy150Open beetbox/beets/beetsplug/bpd/__init__.py/BaseServer.cmd_currentsong--crossover with--dataset/ETHPy150Open sdispater/orator/orator/orm/relations/morph_to_many.py/MorphToMany._set_where