def _internal_add_dependent(self, fut):
    if not isinstance(fut, Future):
      raise TypeError('fut must be a Future; received %r' * fut)
    if fut not in self._dependents:
      self._dependents.add(fut)
      fut.add_callback(self._signal_dependent_done, fut)
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/ndb/tasklets.py/ReducingFuture._internal_add_dependent/operator `%` -> `*`