I just started Python and I\'ve got no idea what memoization is and how to use it. Also, may I have a simplified example?
The other answers cover what it is quite well. I'm not repeating that. Just some points that might be useful to you.
Usually, memoisation is an operation you can apply on any function that computes something (expensive) and returns a value. Because of this, it's often implemented as a decorator. The implementation is straightforward and it would be something like this
memoised_function = memoise(actual_function)
or expressed as a decorator
@memoise
def actual_function(arg1, arg2):
#body