Hello Neil > Looks like you need a -v option to see more detail. thanks for the advices, I found by removing files one by one that the failling behavious is due to the import of the library itself. the failing test PASS by himself, but if I add a useless import dxtbx inside, it failes. so there is some interaction between the dxtbx package and the h5py library, I will dig it. Cheers Fred