The problem is in Pillow, 3.4.0 through 3.4.2. I have a workaround for the OpenSlide Python test suite that I'll get committed and then post here.
- Bug#852502: openslide-python: FTBFS (failing te... Santiago Vila
- Bug#852502: openslide-python: FTBFS (faili... Santiago Vila
- Bug#852502: marked as done (openslide-pyth... Debian Bug Tracking System
- Bug#852502: openslide-python: FTBFS (faili... Benjamin Gilbert
- Bug#852502: openslide-python: FTBFS (f... Benjamin Gilbert
