wrapper.__wrapped__ is func

Decorators & Metaclasses

Meaning

The __wrapped__ attribute of a wrapper function created with functools.wraps refers to the original function that was wrapped.

Primary Function

Provides access to the original wrapped function for introspection, debugging, or calling the undecorated version.

Communicative Purpose

Asserts that the wrapper exposes the original function via its __wrapped__ attribute, enabling introspection.

Função primária

Provides access to the original wrapped function for introspection, debugging, or calling the undecorated version.

Propósito comunicativo

Asserts that the wrapper exposes the original function via its __wrapped__ attribute, enabling introspection.

Situações de gatilho

When using functools.wraps to create a decorator and needing to access the original function, e.g., for debugging, calling the undecorated function, or preserving metadata.

Contextos

Writing decorators, debugging decorated functions, preserving function signatures, accessing the original function from a wrapper.

Família do chunk

functools.wraps
decorator pattern

Dica de memória

Think of __wrapped__ as the original function tucked inside the wrapper.

Nota

The __wrapped__ attribute is set automatically by functools.wraps to point to the original function.

Tag de espaçamento: UnknownIdioma?: Sim

Examples

import functools\n\ndef original(x):\n return x * 2\n\ndef decorator(func):\n @functools.wraps(func)\n def wrapper(*args, **kwargs):\n return wrapper.__wrapped__(*args, **kwargs)\n return wrapper\n\ndecorated = decorator(original)\nassert decorated.__wrapped__ is original

import functools\n\ndef debug(func):\n @functools.wraps(func)\n def wrapper(*args, **kwargs):\n print(f'Calling {func.__name__} with {args}, {kwargs}')\n result = wrapper.__wrapped__(*args, **kwargs)\n print(f'Got {result}')\n return result\n return wrapper\n\n@debug\ndef multiply(a, b):\n return a * b\n\n# Call the original function directly, bypassing logging\nresult = multiply.__wrapped__(3, 4) # returns 12, no print output

import functools\nimport inspect\n\ndef memoize(func):\n cache = {}\n @functools.wraps(func)\n def wrapper(*args):\n if args in cache:\n return cache[args]\n result = wrapper.__wrapped__(*args)\n cache[args] = result\n return result\n return wrapper\n\n@memoize\ndef fib(n):\n return n if n < 2 else fib(n-1) + fib(n-2)\n\n# Verify the signature of the original function via __wrapped__\nsig = inspect.signature(fib.__wrapped__)\nprint(sig) # (n)