pygame for python3

1. Change to your home directory.

   cd ~

2. Get Pygame source code.

   sudo apt-get install mercurial
   hg clone https://bitbucket.org/pygame/pygame
   cd pygame

3. Install dependencies.

   sudo apt-get install python3-dev python3-numpy libsdl-dev libsdl-image1.2-dev \
     libsdl-mixer1.2-dev libsdl-ttf2.0-dev libsmpeg-dev libportmidi-dev \
     libavformat-dev libswscale-dev libjpeg-dev libfreetype6-dev

4. Build and install Pygame.

   python3 setup.py build
   sudo python3 setup.py install