I recently came across Project Euler; for those unfamiliar it is a challenge combining math and programming skills. Unfortunately, I have no programming abilities and as such am unable to solve even the third problem without cheating.

I know how I would like to approach the problem, but not how I can write it in python. The question involves finding the prime factors of a large number (317584931803).

I want to use the functions:
f(x)=number/x
and
g(x)=x-int(x)
to form the composition g(f(x))=f(x)-int(f(x))

and then have it test the values of x when g(f(x))=0 for primeness, and print those values which are prime.

So, in short, how are functions written in python?
Err...and if anyone has time, how would the above be written?

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