CODE EXAMPLE FOR PYTHON

python find which os

# If you want user readable data but still detailed, 
# you can use platform.platform()

>>> import platform
>>> platform.platform()
'Linux-3.3.0-8.fc16.x86_64-x86_64-with-fedora-16-Verne'

# platform also has some other useful methods:
>>> platform.system()
'Windows'
>>> platform.release()
'XP'
>>> platform.version()
'5.1.2600'

# More check the source