Nested f-strings

Question

Thanks to David Beazley\'s tweet, I\'ve recently found out that the new Python 3.6 f-strings can also be nested:

>>> price = 478.23
>>> f\"         


        

Answer 1

Working on a pet project I got sidetracked by writing my own DB library. One thing I discovered was this:

>>> x = dict(a = 1, b = 2, d = 3)
>>> z = f"""
    UPDATE TABLE 
        bar 
    SET 
        {", ".join([ f'{k} = ?'     for k in x.keys() ])} """.strip()
>>> z
'UPDATE TABLE 
    bar 
SET 
    a = ?, b = ?, d = ?  '

I was also surprised by this and honestly I am not sure I would ever do something like this in production code BUT I have also said I wouldn't do a lot of other things in production code.