code: def size(pathname):
      
      if os.path.isfile(pathname):
          return os.path.getsize(pathname)
      return sum([size('{}/{}'.format(pathname, name)) for name in get_content_list(pathname)])
docs: Returns size of a file or folder in Bytes
  
      :param pathname: path to file or folder to be sized
      :type pathname: str
      :return: size of file or folder in Bytes
      :rtype: int
      :raises: os.error if file is not accessible