dynamic f-string example

[Skaperen]

calling it a Frankenstein ... i would agree. but what else is there. i first wrote a function to do it, but that was worse grabbing the caller's namespaces and such. people are going to get used to short code doing f-strings so when they run into a dynamic case, such as reading the format in from a file, they want to do it as close to the same way as they can. i did, too. when i figure it out (was not hard) i decided to share.