Entering a requirements file URL fails with a generic "Couldn't check" error

[edmorley]

STR:

1. Enter https://raw.githubusercontent.com/mozilla/treeherder/b2ecb99390185ed7883b2334c1b11855ddd0811b/requirements/common.txt in the text field on https://caniusepython3.com/
2. Press submit

Expected:
If there were errors (eg due to #47) then they are displayed as part of the error message, eg:

Couldn't check ['https://raw.githubusercontent.com/mozilla/treeherder/b2ecb99390185ed7883b2334c1b11855ddd0811b/requirements/common.txt']: invalid requirement 'https://github.com/jeads/datasource/archive/v0.10.0.tar.gz#egg=datasource==0.10.0'.

Actual:

Couldn't check ['https://raw.githubusercontent.com/mozilla/treeherder/b2ecb99390185ed7883b2334c1b11855ddd0811b/requirements/common.txt'].

[nikolas]

I'm also seeing this error, for example: https://raw.githubusercontent.com/ccnmtl/plexus/master/requirements.txt

[edmorley]

This still repros for me.

[brainwane]

I ran into this today when trying to get the site to check https://raw.githubusercontent.com/jjjake/internetarchive/master/pex-requirements.txt .