Debug line to let users know how long to wait from retry-after

[stephanebruckert]

Context

In spotipy we use urllib3's retry mechanism but many issues have been reported because some calls just "hang" and no feedback is reported back to the user about how long to wait. Sometimes it could be a full hour if the retry-after happens to be 3600 spotipy-dev/spotipy#862 (comment)

See spotipy-dev/spotipy#937 spotipy-dev/spotipy#913 spotipy-dev/spotipy#862 spotipy-dev/spotipy#844 spotipy-dev/spotipy#790

Can we add a debug log to let users know how long to wait?

Alternatives

We can log it without urllib3, building our own retry

Contribution

I can submit a PR but would need to know if you would be OK with adding a debug line around:

urllib3/src/urllib3/util/retry.py

Line 324 in 5a24dc5

time.sleep(retry_after)

[stephanebruckert]

@SethMichaelLarson sorry for the direct mention, I saw you were active.

What do you think of this? Happy to open a PR