Python path for mkdocs

[Benjamin Piwowarski]

Hi,

I would like to add a custom directory (docs/lib) to the Python path, using the mkdocs backend - the reason is that I would like to use a custom markdown extension. Is there any simple way to do that - I tried to add a custom conf.py file, but this seems to be only used by the sphinx backend. 

Thanks for any help,

Benjamin