Add typing to package

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When trying to lint code piece which is using your package with mypy it says that
module is installed, but missing library stubs or py.typed marker

please add those it should be simple according to https://blog.whtsky.me/tech/2021/dont-forget-py.typed-for-your-typed-python-package/#adding-pytyped

[Crozzers]

There's a pending PR that drops Python 3.5, so if that goes through I'd be happy to add some inline type hints for the main user facing API

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Hello how it's going

[Crozzers]

The PR I'm waiting on has received some updates and once it gets merged we can start adding type hints to the package