Add pytest-watcher

[olzhasar]

What is this Python project?

pytest-watcher is a tool to automatically rerun tests (using pytest by default) whenever your code changes. The tool saves a lot of time and is especially useful for TDD practitioners.

Pypi: https://pypi.org/project/pytest-watcher/

What's the difference between this Python project and similar ones?

I believe there are currently no utilities like this in the list. Previously, there was a project called pytest-watch which, unfortunately, is no longer maintained. This project serves as a substitute for it.

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