Issue 21947 informed the `dis` module about the `gi_code` attribute, which stores code objects for generator objects. This allows inspection of generator objects, not just functions which return them. However, asynchronous generator objects use `ag_code` and coroutine objects use `cr_code`, so dis raises a TypeError on them. I'm making a pull request to extend the generator behavior to async generators and coroutines.

Credit to Luciano Ramalho: I tripped over this at his (great) concurrency workshop at PyBay 2017 and he identified exactly what was happening and suggested a patch.