python - str()和直接调用__str__用法有不同吗?

Question

遇到很奇葩的问题,请看贴图:

为什么str(cut)会报错? 但cut.__str__()不会?

Answer 1

You should indicate that this is Python 2.

str is actually a class. Since it is a class, its result should naturally return an instance of type str. So it will try to convert the result of your cut.__str__() (unicode type) into str. An error was reported at this step.