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Functions & basics

Reusable building blocks — parameters, returns, scope, and clear function design.

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Functions & basics medium

How to Invalidate Cache When Arguments Change in Python

A memoization decorator that caches function results keyed by arguments, automatically invalidating when inputs change.

decorators caching memoization
Python 
from functools import wraps

def memoize(func):
    cache = {}
    
    @wraps(func)
    def wrapper(*args, **kwargs):
        key = (args, tuple(sorted(kwargs.items())))
        if key not in cache:
            cache[key] = func(*args, **kwargs)
        return cache[key]
    
    return wrapper

@memoize
def expensiv…
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