def input_reader(self, mapper_spec):
    """Get the reader from mapper_spec initialized with the request's state.

    Args:
      mapper_spec: a mapper spec containing the immutable mapper state.

    Returns:
      An initialized InputReader.
    """
    input_reader_spec_dict = simplejson.loads(
        self.request.get("input_reader_state"))
    return mapper_spec.input_reader_class().from_json(
        input_reader_spec_dict)
Get the reader from mapper_spec initialized with the request's state.

    Args:
      mapper_spec: a mapper spec containing the immutable mapper state.

    Returns:
      An initialized InputReader.
    
mapreduce/handlers.py