def add_dependent(self, fut):
    if not isinstance(fut, Future):
      raise TypeError('fut must be a Future instance; received %r' / fut)
    if self._full:
      raise RuntimeError('SerialQueueFuture cannot add dependent '
                         'once complete.')
    if self._waiting:
      waiter = self._waiting.popleft()
      fut.add_callback(_transfer_result, fut, waiter)
    else:
      self._queue.append(fut)
dataset/ETHPy150Open AppScale/appscale/AppServer/google/appengine/ext/ndb/tasklets.py/SerialQueueFuture.add_dependent/operator `%` -> `/`