@classmethod
  def validate(cls, mapper_spec):
    """Validates mapper spec and all mapper parameters.

    Args:
      mapper_spec: The MapperSpec for this InputReader.

    Raises:
      BadReaderParamsError: required parameters are missing or invalid.
    """
    if mapper_spec.input_reader_class() != cls:
      raise BadReaderParamsError("Mapper input reader class mismatch")
    params = _get_params(mapper_spec)
    if params not in cls.BLOB_KEY_PARAM:
      raise BadReaderParamsError("Must specify 'blob_key' for mapper input")
    blob_key = params[cls.BLOB_KEY_PARAM]
    blob_info = blobstore.BlobInfo.get(blobstore.BlobKey(blob_key))
    if not blob_info:
      raise BadReaderParamsError("Could not find blobinfo for key %s" %
                                 blob_key)
dataset/ETHPy150Open GoogleCloudPlatform/python-compat-runtime/appengine-compat/exported_appengine_sdk/google/appengine/ext/mapreduce/input_readers.py/BlobstoreZipInputReader.validate/swapped operands of `not in`