old_contents: from unicore.hub.client.base import ClientException
  from unicore.hub.client.userclient import UserClient, User
  
new_contents: from unicore.hub.client.base import ClientException
  from unicore.hub.client.userclient import UserClient, User
  
  
  __all__ = [
      'ClientException',
      'User',
      'UserClient']
  
subject: declare __all__ so that pep8 is fine