Cannot install dependencies on 16.0

The minimal python version supported in 16.0 is 3.7

https://github.com/odoo/odoo/blob/16.0/odoo/__init__.py#L18-L21

But we cannot install the documentation dependencies in this version because multiple packages are requiring 3.8

$ uv pip install -r community/requirements.txt -r documentation/requirements.txt pudb ipython
Using Python 3.7.9 environment at: .venv16
  × No solution found when resolving dependencies:
  ╰─▶ Because the current Python version (3.7.9) does not satisfy Python>=3.8 and sphinxcontrib-applehelp==1.0.4 depends on Python>=3.8, we can conclude that sphinxcontrib-applehelp==1.0.4 cannot be used.
      And because you require sphinxcontrib-applehelp==1.0.4, we can conclude that your requirements are unsatisfiable.