windows: add win32com.shell to demandimport ignore list Module 'appdirs' tries to import win32com.shell (and catch ImportError as an indication of failure) to check whether some further functionality should be implemented one or another way [1]. Of course, demandimport lets it down, so if we want appdirs to work we have to add it to demandimport's ignore list. The reason we want appdirs to work is becuase it is used by setuptools [2] to determine egg cache location. Only fairly recent versions of setuptools depend on this so people don't see this often. [1] https://github.com/ActiveState/appdirs/blob/master/appdirs.py#L560 [2] https://github.com/pypa/setuptools/blob/aae0a928119d2a178882c32bded02270e30d0273/pkg_resources/__init__.py#L1369