docs: def load_data_file(path_of_file):
      """ Loads the content of a file by using json.load.
  
      :param path_of_file: the path of the file to load
      :return: the file content as a string
      :raises exceptions.ValueError: if the file was not found
      """
      if os.path.exists(path_of_file):
          return storage_utils.load_objects_from_json(path_of_file)
      raise ValueError("Data file not found: {0}".format(path_of_file))