What is memoization in Python and how can I implement it using decorators?

What is memoization in Python and how can I implement it using decorators?

Memoization is an optimization technique that stores the results of expensive function calls and returns the cached result when the same inputs occur again. In Python, you can implement memoization using decorators.

Can you show me a simple example of a memoization decorator?

Sure! Here's a basic example:

def memoize(func):
    cache = {}
    def wrapper(*args):
        if args in cache:
            return cache[args]
        result = func(*args)
        cache[args] = result
        return result
    return wrapper

@memoize
def fibonacci(n):
    if n <= 1:
        return n
    return fibonacci(n-1) + fibonacci(n-2)

How does this decorator improve performance?

The decorator improves performance by caching the results of function calls. Instead of recalculating the Fibonacci number for the same input multiple times, it retrieves the result from the cache, significantly reducing the number of computations.