old_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  
  from flask import Blueprint
  
  api = Blueprint('api', __name__)
  
  from . import authentication, errors, status, problem, oj_status
  
new_contents: #!/usr/bin/env python
  # -*- coding: utf-8 -*-
  
  from flask import Blueprint
  
  api = Blueprint('api', __name__)
  
  
subject: fix can not test bug