Decorator Removed

[Patil2099]

Fixes #1423

[Patil2099]

@pipermerriam

[kclowes]

@Patil2099 We'll review once all the tests are passing! Thanks!

[Code0x58]

dict_copy does more than work around def f(d={}): reusing the default parameter object.

From the tests (given that dict comparisons are failing), it looks like it is also being relied on to create deep copies of objects so that the code using it can mutate the object without affecting the original object.

It would probably be good to mark dict_copy as deprecated if nowhere in the codebase uses it, then make an issue for it and tag it with the next major release.

You will also need to find where copies are needed to avoid mutating dictionaries the function/code doesn't own. I think keeping on this approach would be better for the code in the long run rather than continuing to rely on dict_copy.

dict_copy has a few issues, including documentation and the name being wrong (they match the intent, but not what it actually does). For example it copies a lot more than just dicts, and any type of mutable object inside them (not just dict/list/tuple/set) will be deep copied. I suspect it didn't copy args just to avoid working around the first parameter of class methods. Killing it with fire sounds good to me.