Opening this separately from #1838 since it seems like a good first issue. Currently, code objects are missing the `co_cellvars` attribute: ```python def foo(a, b): def bar(c, d): print(a, b, c, d) ``` In RustPython: ```python >>>>> foo.__code__.co_cellvars Traceback (most recent call last): File "<stdin>", line 1, in <module> AttributeError: 'code' object has no attribute 'co_cellvars' ``` While in Python: ```python >>> foo.__code__.co_cellvars ('a', 'b') ``` looking at the other methods on [`PyCode`](https://github.com/RustPython/RustPython/blob/1fd557d549cd72e7da83608b99e5464273abd4b3/vm/src/builtins/code.rs#L188) should help, the implementation should be similar to others there that return a tuple.
Activity
Add co_cellvars to code object
Add co_cellvars to code object