Feature or enhancement

Proposal:

Up until Python 3.11, the output of the followingast.parse/unparse run

importastfromsysimportversion_infoasviprint(f"{vi.major}.{vi.minor}.{vi.micro}")print(ast.unparse(ast.parse("f\"{'.' * 5}\"")))

was

3.11.11f"{'.' * 5}"

In Python 3.12,new f-string features were introduced, allowing for more general quote combinations. The output of the above script in Python 3.12 and 3.13 is

3.12.7f'{'.' * 5}'

While this is legal Python 3.12/3.13, this representation needlessly restricts the usability of the generated code: It will not work on Python 3.11 and earlier.

I would thus like to suggest forast.unparse to return, if possible, the more compatible code; in this case

f"{'.' * 5}"

which works across all currently supported Python versions.

Has this already been discussed elsewhere?

No response given

Links to previous discussion of this feature:

No response

Linked PRs

• gh-127975: Avoid reusing quote types in ast.unparse if not needed #127980
• [3.13] gh-127975: Avoid reusing quote types in ast.unparse if not needed (GH-127980) #129600
• [3.12] gh-127975: Avoid reusing quote types in ast.unparse if not needed (GH-127980) #129601