[issue31907] Clarify error message when attempting to call function via str.format()

[mickey695]

mickey695 <mickey695 at gmail.com> added the comment:

I think it should be documented properly.

In roughly two weeks I will have some time to look into it. 
So I could probably document the current behaviour by the start of December(unless someone beats me to it)

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Python tracker <report at bugs.python.org>
<https://bugs.python.org/issue31907>
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