At the very least, it could serve as a widely adopted reference (Atom, Sublime, and VS Code use it).
I also wrote a very naive and wrong hack for personal use, based on php-mode:
```
(defconst python-f-string-regexp
"{[[:word:]]+\\.?[[:word:]]+?}")
(defun python-f-string-font-lock-find (limit)
(while (re-search-forward python-f-string-regexp limit t)
(when (python-syntax-comment-or-string-p)
(put-text-property (match-beginning 0) (match-end 0)
'face 'font-lock-variable-name-face)))
nil)
(with-eval-after-load 'python
(font-lock-add-keywords
'python-mode
`((python-f-string-font-lock-find))
'append))
```
(I'm really sorry, I don't know how to format monospaced text in debbugs)