Hi,

The overall picture is powered by #7105:

Background:

For a number of years, NV Access and the community have been thinking about moving NVDA's source code to Python 3. The prerequisite for this work has been preparation of Python 3 versions of various dependencies, the biggest ones being wxPython, SCons, py2exe, ConfigObj and many others.

In July 2018, NVDA was switched to use wxPython 4.0.3, a milestone in Python 3 transition planning. This lays the theoretical foundation to transitoin to Python 3, specifically Python 3.7. As noted in issue #7105, NVDA 2018.3 is considered "version N", with research and porting to take place in the very near future (ideally throughout 2019).

Specific issue at hand:

At the moment NVDA imports Python 2 versions of various modules. However, in Python 3, some of them are renamed. The most notable case being "_winreg", which has been renamed to "winreg" (without the underscore). Some fragments use aliased import (of the form "import _winreg as winreg"), while others import this module directly. There are other renamed modules, but winreg is the most notable one.

Thus it is proposed to do two things:

1. Unify the import statements.
2. Try importing Python 3 name first, and if it fials, resort to Python 2.

Applying this to _winreg:

Old:

import _winreg

New:

try:
  import winregexcept ImportError:
  import _winreg as winreg

Which then allows winreg functions and attributes to be accessed via Python 3 name.

Note that for the rest of the template, because this issue concerns future work, most fields are not applicable.

Steps to reproduce:

Import various modules that have both Python 2 and 3 implementations, or are renamed in Python 3.

Name and version of other software in use when reproducing the issue:

Python 2.7.15, Python 3.7.0