You can't generate real-random numbers in software alone. Real random number generation relies on sampling some random physical process. Google "real random number" and you'll find a number of online sources of genuine random numbers, including random.org (which uses atmospheric noise) and hotbits (which uses radioactive decay).

For the interested, the pseudorandom number generator in NumPy implements the Mersenne Twister, which is generally considered a good generator for many applications, and is also used by the Python standard library's random module, as well as R, Maple, Ruby and recent versions of MATLAB.