Unable to set default python version to python3 in ubuntu

Question

I was trying to set default python version to python3 in Ubuntu 16.04. By default it is python2 (2.7). I followed below steps :

Answer 1

The second line mentioned can be changed to

update-alternatives --install /usr/bin/python python /usr/bin/python3 10

This gives a priority of 10 for the path of python3. The disadvantage of editing .bashrc file is that it will not work while using the commands with sudo.

Update: Please use sudo while running the command like this:

sudo update-alternatives --install /usr/bin/python python /usr/bin/python3 10