def __init__(self, batcher):
    if not isinstance(batcher, Batcher):
      raise datastore_errors.BadArgumentError(
          'batcher argument should be datastore_query.Batcher (%r)' %
          (batcher,))

    self.__batcher = batcher
    self.__current_batch = None
    self.__current_pos = 0
Constructor.
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/datastore/datastore_query.py/ResultsIterator.__init__