BUG: ensure that docstrings in classes from astropy.io.ascii are always available for inspection at runtime - #17556

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I don't quite understand why only the classes in basic.py get the __doc__ = change. What about all the other Reader classes? https://astropy--17556.org.readthedocs.build/en/17556/io/ascii/ref_api.html#classes

That's just because I lack a systematic way to look for child classes. This table will do, thanks !

Closing this following discussion over at #17555