bpo-34789: make xml.sax.make_parser accept iterables of all types

[andresdelfino]

https://bugs.python.org/issue34789

[taleinat]

This would be a great opportunity to change the default value for parser_list from [] to something immutable, e.g. an empty tuple. (Using mutable default values is a Bad Idea™!)

[andresdelfino]

@taleinat yes, I think you are right. My last commit addresses this suggestion too.

[taleinat]

LGTM

[miss-islington]

@andresdelfino: Status check is done, and it's a failure ❌ .

[miss-islington]

@andresdelfino: Status check is done, and it's a failure ❌ .