- Updated Lib/collections from CPython v3.14.3
- Preserved RustPython's fallback implementation for defaultdict
- Added test for update_reentrant_add_clears_counter
- Minor formatting fixes in test file
Co-authored-by: CPython Developers <>
Clean implementation of changes in PR #3371 based on feedback.
Copies from [CPython tag `v3.9.7` and adds back custom RustPython changes where needed for:
- `Lib/collections/__init__.py`
- `Lib/test/test_collections.py`
Closes: #3371