[raverbashing]

Not the docs, the library code is (for the most part) automatically generated

This is actually a good example of how the thing works, you have to use MessageBody as an argument name to send the message. Or use the Entries argument

Those names and that usage style are far from Pythonic

[ArchOversight]

They map to the underlying JSON calls that are made. It's like they took the top-level keys of the JSON and made them kwargs in the Python.