def __init__(self, *events):
        super(EventUnion, self).__init__()
        self.events = events
Yields (text, doc_freq, index_freq) tuples for all terms
dataset/ETHPy150Open mozilla/django-tidings/tidings/events.py/EventUnion.__init__--crossover with--dataset/ETHPy150Open dokipen/whoosh/src/whoosh/reading.py/IndexReader.iter_field