Monkeypatch dataclasses so that its generated code becomes debuggable

[inducer]

The difficulty here is going to be to do this reasonably robustly, perhaps by explicitly listing Python versions for which it is OK. All that's necessary is to patch this function:

https://github.com/python/cpython/blob/d71f5adc41569c2d626552269797e0545fc9122c/Lib/dataclasses.py#L413-L436=