大家可以看看菜鸟教程，里面已经很全面了。
https://www.runoob.com/
类：
https://www.runoob.com/python/python-object.html
https://www.runoob.com/python3/python3-class.html
异常：
https://www.runoob.com/python/python-exceptions.html
https://www.runoob.com/python3/python3-errors-execptions.html
2020-04-12