class User:
  '用户类'
  userCount = 0

  def __init__(self, username):
    self.username = username
    User.userCount += 1
  
  def __del__(self): 
    classname = User.__name__
    print('class: ', classname, '销毁成功')

  def display(self):
    print('User: ', self.username, ', User.Count', User.userCount)

user1 = User('python user')
user1.display()
print('user doc', User.__doc__, User.__module__, User.__dict__)