Python-Heroku - aiohttp 3.7.3 has requirement chardet<4.0,>=2.0, but you'll have chardet 4.0.0 which is incompatible

I had the same issue but managed to fix it by specifying the version of chardet in requirements.txt as 3.0.4

chardet==3.0.4

and then simply run

pip install -r requirements.txt

and everything will work out just fine.

Note that you'll also get that error if you're using in your requirements.txt the following version of chardet

chardet==4.0.0

CodeHunter