### What needs to get done ## Situation The [`python-requirements` key](https://canonical-craft-parts.readthedocs-hosted.com/latest/common/craft-parts/reference/plugins/python_v2_plugin/#python-requirements) in the Python plugin references doesn't make it clear when it comes into play with the various dependency mechanisms: `requirements.txt`, `setup.cfg`, and `pyproject.toml`. Notably, it's not completely clear when a part _doesn't_ need to use the key. ## Request Update all Python plugin refs to describe the conditions of the key in more detail. ### Why it needs to get done More accuracy and completeness for the Python plugin reference.