ContributorGuidelines

This is placeholder for contributor guidelines.

1. Golden rule: Please do "git log"/"git log -p" and follow the same approach with your changes. Some specifics:
2. One changed module/package per commit.
3. Every commit message starts with "<module>:"
4. Each module's setup.py is autogenerated from metadata.txt by make_metadata.py script, so please make changes to metadata.txt, run make_metadata.py and then commit both metadata.txt and setup.py.
5. Name something "test_.py" only if it's real unittest (which will checks results itself and will fail if there's error). Otherwise if human should check test results, name it "example_.py"

When porting a module from CPython or other 3rd-party source:

1. Start with committing 3rd-party source as-is, clearly stating in commit message from where it was taken (exact version, preferrably with URL to tarball, or VCS revision, preferrably with URL to it).
2. Follow up with your changes as a next commit.
3. When doing your changes, the criteria should be minimizing size of diff. Change as few lines as possible, within lines, don't change more chars than needed. Prefer commenting out to removal of lines. Don't fix typos, etc. - if you want them to be fixed, submit patches directly to upstream.
4. Prefer taking (and porting) test from CPython rather than duplicate effort and making your own.