random.shuffle operates on a list, and changes it in place. I think returning a reference to this list, the same one we got in as the argument, is quite useful and makes it possible to use random.shuffle in chained function calls, e.g.:

somelist.append(''.join(shuffle(list('hello'))))
[i for i in shuffle(list(range(10))) if i%2]

I don't see any good arguments against this, and I couldn't think of a reasonable test for this — is it necessary to test whether the returned reference is the same as the one passed in?

I'm open to any discussion or suggestions you might have.