I updated the PR to take in a sequence of separators from the user - eg:

>>> urllib.parse.parse_qsl('a=1&b=2;c=3', separators=('&', ';'))
[('a', '1'), ('b', '2'), ('c', '3')]
>>> urllib.parse.parse_qsl('a=1&b=2;c=3', separators=('&',))
[('a', '1'), ('b', '2;c=3')]

I _didn't_ change the default - it will allow both '&' and ';' still. Eric showed a link above that still uses semicolon. So I feel that it's strange to break backwards compatibility in a patch update. Maybe we can make just '&' the default in Python 3.10, while backporting the ability to specify separators to older versions so it's up to users?

I'm not sure, any thoughts on this? Opinions would be greatly appreciated.