#18600: add policy to add_string, and as_bytes and __bytes__ methods.
This was triggered by wanting to make the doctest in email.policy.rst pass; as_bytes and __bytes__ are clearly useful now that we have BytesGenerator. Also updated the Message docs to document the policy keyword that was added in 3.3.
R
R David Murray committed
bb17d2b857d33e474f830c4a665f1fa412eb29f1
Parent: 3f58277