Python 3.9.0a0 (heads/bpo-31722:fc4a044a3c, Oct  4 2019, 03:10:14)
[Clang 11.0.0 (clang-1100.0.33.8)] on darwin
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>>> import functools
>>> def f():
...     def g():
...         yield 1
...     return g
...
>>> functools.partial(f())().__qualname__ == f()().__qualname__
True
>>> functools.partial(f())().__qualname__
'f.<locals>.g'
>>> f()().__qualname__
'f.<locals>.g'

Looks like that this issue is fixed