- Add CO_NESTED flag (0x10) for nested function scopes
- Emit LOAD_SMALL_INT for integers 0..=255 instead of LOAD_CONST
- Eliminate dead constant expression statements (no side effects)
- Ensure None in co_consts for functions with no other constants
- Add code.__replace__() for copy.replace() support
- Mark test_co_lnotab and test_invalid_bytecode as expectedFailure
* Downgraded skips in tests
* Fixed failing tests
* Fixed test_ftplib + test_socket + test_ssl + test_threaded_import failures
* Removed comments about which tests are run in which environment
* Addressed PR comments
* Annotated skips on failing tests
* Removed unneeded tests
* Removed unneeded sys import from test_ftplib
* Added annotation to test_ftplib
* Readded skipIf to test_cleanup_with_symlink_modes with a more general ENV_POLLUTING_TESTS_WINDOWS
* Addressed PR comments
* Made changes to minimize diff in PR
* Apply suggestion from @youknowone
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Co-authored-by: Jeong, YunWon <69878+youknowone@users.noreply.github.com>