Contributed by Marc Mueller (PR[20156](https://github.com/python/mypy/pull/20156)).

Removed the deprecated`--force-uppercase-builtins` flag. It has been a no-op since mypy 1.17.0.

The`--force-uppercase-builtins` flag was deprecated and has been a no-op since mypy 1.17.0.

Since mypy has dropped support for Python 3.9, the`--force-union-syntax` flag is no longer

necessary.

Contributed by Marc Mueller (PR[20410](https://github.com/python/mypy/pull/20410))

Mypy only supports Python 3.10+. Removed the`--force-union-syntax` flag as it's no longer necessary.

Contributed by Marc Mueller (PR[20405](https://github.com/python/mypy/pull/20405))

and (PR[20405](https://github.com/python/mypy/pull/20405)).

Please see[git log](https://github.com/python/typeshed/commits/main?after=ebce8d766b41fbf4d83cf47c1297563a9508ff60+0&branch=main&path=stdlib) for full list of standard library typeshed stub changes.

- Fix noncommutative joins with bounded TypeVars (Shantanu, PR[20345](https://github.com/python/mypy/pull/20345))

- Respect output format for cached runs by serializing raw errors in cache metas (Ivan Levkivskyi, PR[20372](https://github.com/python/mypy/pull/20372))

- Allow`types.NoneType` in match cases (A5rocks, PR[20383](https://github.com/python/mypy/pull/20383))

- Fix mypyc generator regression with empty tuple (BobTheBuidler, PR[20371](https://github.com/python/mypy/pull/20371))

- Fix crash involving Unpack-ed TypeVarTuple (Shantanu, PR[20323](https://github.com/python/mypy/pull/20323))

- Fix crash on star import of redefinition (Ivan Levkivskyi, PR[20333](https://github.com/python/mypy/pull/20333))

- Fix crash on typevar with forward ref used in other module (Ivan Levkivskyi, PR[20334](https://github.com/python/mypy/pull/20334))

- Fail with an explicit error on PyPy (Ivan Levkivskyi, PR[20389](https://github.com/python/mypy/pull/20389))

Thanks to all mypy contributors who contributed to this release:

I’d also like to thank my employer, Dropbox, for supporting mypy development.

We’ve just uploaded mypy 1.18.1 to the Python Package Index ([PyPI](https://pypi.org/project/mypy/)).

Mypy is a static type checker for Python. This release includes new features, performance