@abc.abstractmethod
    def on_assignment(self, assignment):
        pass
Should return a sequence of TrackInfo objects that match the
dataset/ETHPy150Open dpkp/kafka-python/kafka/coordinator/assignors/abstract.py/AbstractPartitionAssignor.on_assignment--crossover with--dataset/ETHPy150Open beetbox/beets/beets/plugins.py/BeetsPlugin.item_candidates