###version 1.0
Super simple code I used out of personal need. I have directory with hundreds of subfolders out of which many had dates as names. But dates were in a wrong format - mostly "D.MM.YYYY" which everyone will agree was not a good idea. The best format is ISO format: "YYYY-MM-DD". Oldest folders are dated back to 2008, the time when I didn't knew how bad this idea was. Because of my stubbornness, I kept with once given format for many years, resulting with hundreds of ugly folder names.
Finally, the time has come. I didn't wanted to do it manually, therefore here's the code. Take it, use it, adjust it and remember - the only correct date format is ISO format.
Cheers!
If you want to adjust the code for your need, start with line 26 where I've hardcoded date formats:
patterns = [
'%d.%m.%Y', # DD.MM.YYYY
'%Y.%m.%d' # YYYY.MM.DD
]