docstrings and ValueError messages. Patch by Zhongyue Luo

now working with comment block selections. Patch was part of 18226 patch.

Move comment code to a separate function so it can be separately tested.
Original patches by Todd Rovito and Phil Webster.

Before this patch it would raise an error when trying to display
documentation for a method that used annotations.

Patch by Claudiu Popa.

Also, document the policy keyword that was added to Message in 3.3.

#18581: remove duplicate test and run a test class that was skipped.  Initial patch by Vajrasky Kok.

#18273: move the tests in Lib/test/json_tests to Lib/test/test_json and make them discoverable by unittest.  Patch by Zachary Ware.

Patch by Madison May.

on OS-X. Patch by Jeff Ramnani.

Thanks to Stefan Behnel for the report and proposed solution & test.