See SIMPLY-3477 for context.

Version 1.25 of urllib3 makes a change that means you might request a certain URL and have the request made to a slightly different URL:

https://github.com/urllib3/urllib3/pull/1487

We interact with servers where this difference makes the difference between success and failure. So we need to work around this change somehow.

For now we're doing it by pegging urllib3 to 1.24, but this won't work even in the medium term, after we upgrade to Python 3.

It does seem possible to add a hook to urllib3 that sets the URL back to what it was originally before the request goes out – that's probably our best bet.