Can't find version of canonicaljson for Python 3.5

[mythmon]

canonicaljson (which works on Python 3.5) can't be found with pypi2nix. Running pypi2nix -V 3.5 -e canonicaljson produces the error Could not find a version that satisfies the requirement canonicaljson.

[garbas]

for future ... can you run with "pypi2nix -v ..." to get more verbose view (like before 1.4.0 version)

[garbas]

i've checked cannonicaljson and it looks it only has whl as a release. i'm not yet sure how to support whl files. for now source tarballs are required.

i'll leave this ticket open to provide better error messages for this kind of errors.