I see. But the problem is that nobody knows what `something[0][1][0]` means. There's even an anti-pattern name for it, called [Magic Number](http://sourcemaking.com/refactoring/replace-magic-number-with-symbolic-constant).

Also, this may help you a bit: http://www.voidspace.org.uk/python/mock/examples.html#more-complex-argument-matching