1.r"D:\example\test.txt"
2."D:\\example\\test.txt"
3."D:/example/test.txt"
1.r"D:\example\test.txt"
2."D:\\example\\test.txt"
3."D:/example/test.txt"
class MetaCls(type): def __new__(cls, *args, **kwargs): print("in MetaCls") # return super(Meta