Ubuntu 14.04 LTS and Python 3.4.2

1. Download the 3.4.2 source files from here
2. Extract it to a temporary directory within your Downloads folder
3. Open a terminal session.
4. Navigate to the folder with cd ~/Downloads/Python-3.4.2

5. As per the Python documentation, run the following commands from the terminal:

   ./configure
   make
   make test
   sudo make install
   

This will upgrade your existing Python-3.4 installation to Python-3.4.2 (accessible as python3)

You can also use pyenv as your python manager. pyenv

It will allow you to install any version of python, pypy, python3, stackless etc.

it uses shims and also has a nice plugin for virtualenv which makes it a very easy option to use pyenv-virtualenv

Very simple installation.

curl -L https://raw.githubusercontent.com/yyuu/pyenv-installer/master/bin/pyenv-installer | bash

find out which versions are available to install

$ pyenv install --list

install python 3.4.2

sayth@sayth-TravelMate-5740G:~/scripts$ pyenv install 3.4.2
Downloading Python-3.4.2.tgz...
-> https://www.python.org/ftp/python/3.4.2/Python-3.4.2.tgz 
Installing Python-3.4.2...