自己创建的文件名不能叫abc.py，不然会报如下错误
Fatal Python error: init_sys_streams: can’t initialize sys standard streams
Python runtime state: core initialized
Traceback (most recent call last):
File “D:Anacondalibio.py”, line 72, in
AttributeError: module ‘abc’ has no attribute ‘ABCmeta’
参考：
If you name your file abc.py you’re shadowing the standard library’s abc (abstract base class). When you do that, everything that depends on the built-in abc will get yours instead. Unless you’ve essentially rewritten the standard library’s code, things will break.
– Ernst Jun 28, 2018 at 9:57
