functools
functools provides higher-order function utilities: lru_cache, partial, reduce, and wraps.
Python
Intermediate
4 min read
functools Module
Example
from functools import lru_cache, partial, reduce, wraps
@lru_cache(maxsize=256)
def fibonacci(n: int) -> int:
if n < 2: return n
return fibonacci(n-1) + fibonacci(n-2)
double = partial(lambda x, n: x * n, n=2)
total = reduce(lambda a, b: a + b, [1, 2, 3, 4, 5]) # 15
def decorator(fn):
@wraps(fn) # preserves __name__, __doc__
def wrapper(*args, **kw): return fn(*args, **kw)
return wrapper Pro Tip
Always use @wraps in decorators — without it, the wrapped function loses its identity for debugging.