* Note from @jerome: We have a useless dependency to
 https://pypi.org/project/alabaster/, a sphynx theme,
 but with oic v0.15.1 it's listed as a dependency
 ( https://github.com/OpenIDC/pyoidc/blob/v0.15.1/setup.py#L89 )
 so we don't have a choice. It was fixed later
 ( https://github.com/OpenIDC/pyoidc/issues/598 )
 but after python2 support was dropped.