Also not a fan. The two existing methods of string formatting are sufficient:

    "%s %s %s" % (a, b, a)
    "{} {} {}".format(a, b, a)

If you want placeholders to match variable names, you can do:

    "{a} {b} {a}".format(a=a, b=b)
    "{a} {b} {a}".format(**locals())

So this is just unnecessary (especially since the "f" prefix is easier to miss than a "format" method):

    f"{a} {b} {a}"

And this is downright obfuscated—putting operators inside of string literals:

    f"{a + ' ' + b + ' ' + a}"