Why are most Python dependencies use depends_lib?

[Ryan Schmidt]

On Sep 7, 2018, at 22:08, Chih-Hsuan Yen wrote:

> Thank you both for explanations and reasoning! As depends_run and
> depends_lib are practically the same for Python ports, how about
> moving all ports to either depends_lib or depends_run gradually?
> Having two patterns hurts my eyes :D
> 
> If we are moving to depends_run, just remember to keep non-Python
> dependencies in depends_lib for Python packages with C extensions. For
> example, in py-openssl, path:lib/libssl.dylib:openssl should be kept
> in depends_lib and port:py${python.version}-cryptography and
> port:py${python.version}-six can be moved to depends_run.

I do not know enough about Python to confirm whether such a mass change would be appropriate. I thought some Python modules are compiled. If one compiled Python module depends on another compiled Python module, probably it does so at build time, not just at runtime; in other words, depends_lib would be correct for that case.