In Sphinx v4.3.0 and Python 3.8.2, docstrings for type aliases are not captured for primitive aliases, but are for typing.Union aliases.
To produce, install Sphinx into your Python environmen (e.g., pip install sphinx), then:
cd docs
make htmlThen view the generated html for the module at: docs/build/html/testmod.html.
The aliases testmod.FieldInt and testmod.FieldInt2 are listed but their docstrings are not included.