I have recently get hold of a RackSpace Ubuntu server and it has pythons all over the place: 

iPython in 3.5, Pandas in 3.4 &2.7, modules I need like pyodbc etc. are only in 2,7

Therefore, I am keen to clean up the box and, as a 2.7 users, keep everything in 2.7. 

So the key question is, is there a way to remove both 3.4 and 3.5 efficiently at the same time while keeping Python 2.7?
['https://Stackoverflow.com/questions/34198892', 'https://Stackoverflow.com', 'https://Stackoverflow.com/users/4779515/']
**EDIT:** As pointed out in recent comments, this solution may **BREAK** your system.

***You most likely don't want to remove python3.***

Please refer to the other answers for possible solutions.

*Outdated answer (not recommended)*

> 
>  sudo apt-get remove 'python3.\*'
> 
> 
>
neither try any above ways nor `sudo apt autoremove python3` because it will remove all gnome based applications from your system including gnome-terminal. **In case if you have done that mistake and left with kernal only than try`sudo apt install gnome` on kernal.**

try to change your default python version instead removing it. you can do this through **bashrc file** or **export path** command.