Remove EOL Python code, set 3.9 as base, add 3.14 stdlib module (#317)

* Remove redundant Python 2 code

* Use Python 3.2 as base version

* Use Python 3.3 as base version

* Use Python 3.4 as base version

* Use Python 3.5 as base version

* Use Python 3.6 as base version

* Use Python 3.7 as base version

* Use Python 3.8 as base version

* Use Python 3.9 as base version

* Add annotationlib for Python 3.14

* Fix syntax error

Update versions-manifest (#335)

Co-authored-by: Service account <[email protected]>

Update versions-manifest (#335)

Co-authored-by: Service account <[email protected]>

Update versions-manifest (#335)

Co-authored-by: Service account <[email protected]>

Update versions-manifest (#335)

Co-authored-by: Service account <[email protected]>

Update versions-manifest (#335)

Co-authored-by: Service account <[email protected]>

Update versions-manifest (#335)

Co-authored-by: Service account <[email protected]>

Update versions-manifest (#334)

Co-authored-by: Service account <[email protected]>

Update versions-manifest (#333)

Co-authored-by: Service account <[email protected]>

Update versions-manifest (#333)

Co-authored-by: Service account <[email protected]>