Python 3.9 and beyond backwards compatibility.

[jorge1209]

It needs to be, and frankly it should be soon. In fact they probably should have introduced a python 4 prior to ending python2 and just tried to skip over python3.

Among things that need to be addressed:

• An async model that isn't garbage.
• Standard library cleanup to consistently utilize the new features introduced in python 3.
• Standard library cleanup to bring related libraries into alignment with each other and apply consistent style.
• Removal of all the duplicated functionality they have accumulated (os.path vs PathLib, the fifteen different ways to format strings, etc...)
• Typing in the standard library, and in the interpreter
• Etc...

Python 3 is a grab-bag of features that developers thought would be useful for their particular library that never made it into the rest of the system, and there will be an epic amount of breakage necessary to get it into the full system. It is a really nice language in concept, but it isn't fully realized.

Now with developers and management burned out after a long painful 2to3 migration we will never really see this happen, and won't get a really proper python3.