Some time ago, I had to implement a particular C-runtime random number generator in Python. That’s not difficult to do, you just need a variable that maintains the state (seed) of the random number generator, and then you use a simple algebraic expression: a linear congruential generator.
What’s more difficult to figure out, is knowing which multiplier (a) and increment (c) you need to reproduce the particular C-runtime random number generator.
Fortunately, I discovered that Wikipedia has a table with a and c values for many C compilers and other languages: parameters in common use.
Didier Stevens 