Attracted by Python's powerful built-in libs, I learned it by myself. However, its naming convention is confusing me. It even can't correspond to itself in an object. For example, a dict object has a method named has_key and a method named popitem. So I need to check up on the function names frequently.

You should switch to python 3 then. (It fixed most of the crap).

@ItsNotMyFault Oh. It seems I am out of date. I just thought Python2.x was more widely used.

Software often lives for a very long time and since python 3 broke backwards compatibility (necessary to get rid of the mistakes made in previous versions instead of ending up like PHP) there isn't a smooth upgrade path, projects started on Python 2.x need to be partially rewritten to work with Python 3.x (since things like has_key doesn't exist anymore).

If you are starting a new project today you should probably use Python 3.6. (support for 2.7 ends in 2020, libraries like django will have their last release supporting 2.x this year after which it will be 3.x only)

@ItsNotMyFault ok. I guess I have to switch now.

@Pythoneer Thanks. Advice taken.

@Pythoneer Thank you so much! I'm doing this immediately.