boto/boto — pull request #1893 by msilvey (2013-12-05 22:20:09+00:00)
Title: Quick solution to issue 1874. 

Make AssociateAddress return an object with the Association ID instead of a boolean status.

I'm not sure how intrusive a change this would be for the regular/supported use cases of Boto. Anyone who depends on the boolean response will need to change their expected return values.