`ssl.PROTOCOL_SSLv23` has been deprecated since python 3.6 https://docs.python.org/3/library/ssl.html#ssl.PROTOCOL_SSLv23 These are currently [identical values](https://github.com/dpkp/kafka-python/blob/f19e4238fb47ae2619f18731f0e0e9a3762cfa11/kafka/conn.py#L465), but should be addressed?