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Changes between Initial Version and Version 2 of Ticket #37366

initial	v2
1	1	mysqlclient is the "recommended choice", in bold in the docs, but it turns out that it is not compatible with gevent, since gevent cannot monkey-patch the networking code inside the native binary. I want to update the docs to point that out and also add the pure-Python `PyMySQL` library as an additional driver that is compatible with gevent.
	2
	3	I discovered this after several years using mysqlclient and gunicorn together (with gevent workers), due to concurrency problems. The root cause was difficult to diagnose and these proposed docs would have helped.