This amazing tool not only decodes utf-8 but utf-8 in octal form!!!
So if there's any wierd stuff like this in a file (no idea where you would find a file like that):
\x63\x6F\x6F\x6C
\143\157\157\154
\x63\x6F\157\154
\143\157\x6F\x6C
git clone https://github.com/vincuska/utf8-octal-decoder
cd utf8-octal-decoder
python decoder.py