1sudo update-alternatives --install /usr/bin/python python /usr/bin/python3.4 1
2sudo update-alternatives --install /usr/bin/python python /usr/bin/python3.6 2
3
1#Check available versions
2ls /usr/bin/python*
3#Change the used version 3.5 or 3.7 etc
4alias python='/usr/bin/python3.x'
5#do this other thing
6. ~/.bashrc
7#Check version
8python --version
1[sudo] update-alternatives --install /usr/bin/python python /usr/bin/python3 10
2