new_contents: # -*- coding: utf-8 -*-
  
  
  class Error(Exception):
      """Base Error class."""
      pass
  
  
  class APIError(Error):
      pass
  
  
  class APIConnectionError(Error):
      pass
  
  
  class ValidationError(Error):
      pass
  
  
  class AuthorizationError(Error):
      pass
  
subject: define exception class