Most Linux distributions have Python 3.4 preinstalled. You may confirm this by typing python3 in the Terminal. If you see the following, it means Python 3.4 is present:

Python 3.6.3 (default, Oct 6 2017, 08:44:35) [GCC 5.4.0 20160609] on linux Type "help", "copyright", "credits" or "license" for more information. >>>​

If the Python shell does not appear at the command, you can install Python 3 with apt, the Linux software management tool:

sudo apt update
sudo apt install Python3 build-essential

The build-essential package contains compilers that are useful for building non-pure Python packages. Meanwhile, you may need to substitute apt with apt-get if you have Ubuntu 14.04 or older.