There are errors in your install prerequisites
Python 3.6 should be python3.6

Also, I had a problem installing pycurl, so do this first:
sudo apt install libcurl4-openssl-dev libssl-dev
then
python3.6 -m pip install pycurl

Another problem when I run it:
FileNotFoundError: [Errno 2] No such file or directory: '/home/drak/SteemYaLater/Backups/drakos'

So I created that folder manually, then I run the tool again, it fetches the posts but when it starts downloading them, it spits out binary characters on the screen. Did you test this tool properly?