The latest release of the MongoDB's official Python driver, PyMongo 3.9.0, is now available.
The new version comes with support for the newly released MongoDB 4.2.
That includes support for MongoDB 4.2's distributed transactions, with retryable reads and writes enabled by default. Other highlights include the driver's ability to poll DNS SRV records and update the mongos proxy list without the application having to change configuration.
A full list of the changes in 3.9 is available in the PyMongo Changelog.