python build environemnt Leap 15.3

Hi, I needed to branch the package python-cairocffi from d:l:p into a local repository, in order to build it for Leap 15.3 Build fails with the error message: buildinfo is broken... it says: unresolvable: nothing provides if nothing provides (%python-base without python36-base) This probably comes from the line BuildRequires: %{python_module numpy if (%python-base without python36-base)} Can anyone guide me what needs to be tweaked? Thanks Axel