// Libraries

functools

Key FeatureFunction MemoizationDecorator Example@total_orderingOptimization Toollru_cache

The functools module in Python is a standard library module that provides higher-order functions and tools for working with callable objects. It supports functional programming by offering utilities to modify, extend, and optimize the behavior of functions and methods without altering their core logic. This allows for cleaner, more efficient, and reusable code.

Key features of functools include tools for creating partial functions, function memoization with lru_cache, and decorators for method caching. The lru_cache decorator is particularly useful for optimizing recursive functions by caching the results of the most recent calls. The module also offers utilities for comparing and ordering, such as the @total_ordering decorator, which reduces boilerplate when implementing rich comparisons. Furthermore, functools includes the reduce function for performing cumulative operations on data collections.

The functools module is valuable for tasks such as creating functions with fixed arguments, optimizing functions with caching, transforming comparison functions for sorting, and performing cumulative operations on data collections. It also provides the update_wrapper() function, which is used in decorator functions to preserve the metadata of the original function. The module can be used to fix some method arguments when defining methods inside classes without making a new method manually.

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last updated Nov 21, 2025

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Often Mentioned Together

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last updated Nov 21, 2025

Beyond State Overwriting: Implementing Event Sourcing in Python

Designing Robust Python Functions: Beyond the Basics

The Ultimate Guide to Writing Clean Python Classes

Clean Code Architecture: A Masterclass in Writing Better Functions

Often Mentioned Together

Sources