Hi, A recent change "make html" in the Doc directory create a venv if one wasn't there before. If you don't want to download sphinx and other dependencies from PyPI, you'll need to adjust your workflow.
If you already have all the dependencies, the following command (in the CPython directory, not Doc) will build docs for you: sphinx-build Doc Doc/build/
The issue that added this is: https://bugs.python.org/issue44756