Non standard unicode characters

[CarlosGEA]

First of all this file is great, extremely useful stuff.
However, I tried running this file and I was getting an error of the type 'charmap' codec can't encode character '\u0144' in position 278: character maps to ' as I had a polish name with polish characters in one of my .nbib files. I changed line 61 to 'with open(f'bibs/ref.bib', 'w', encoding="utf-8") as output:' and it seemed to work. Just wanted to let you know.