I agree with Raymond: -1 from me.  There isn't a consensus on what "mock 
object" means*, and trying to provide a standardised mock object 
facility is a quagmire*, hence the prior rejections to which Raymond 
refers.

It's easy to roll your own simple mock objects as needed, e.g. for 
whichever Python regression tests might need them.


* Note, for instance, that mock object libraries variously provide 
support for record/playback of calls, partial replacement of methods in 
existing classes or instances, and subtle distinctions between "stubs" 
and "mocks".  I'm aware of at least three wildly different yet equally 
popular mock object libraries in the Java world, each with its own 
uniquely opinionated user base.