code: def check_file_size(file_size, path):
          
          stat_info = os.stat(path)
          if stat_info.st_size != file_size:
              format_str = "Error occurred downloading {}. Got a file size {}. Expected file size:{}"
              msg = format_str.format(path, stat_info.st_size, file_size)
              raise ValueError(msg)
docs: Raise an error if we didn't get all of the file.
          :param file_size: int: size of this file
          :param path: str path where we downloaded the file to