All 15 functools & Functional Programming Tools questions
More in functools & Functional Programming Tools
What is the functools module used for in Python? What is the difference between functools.cache and functools.lru_cache? How does functools.partial work and when is it useful? What does functools.reduce do, and why is it often discouraged in favor of loops? How does @functools.wraps preserve metadata when writing decorators? How does functools.total_ordering reduce boilerplate for comparison methods? What does functools.reduce's initializer argument do, and why should you usually provide one? What is the practical difference between using functools.reduce and a plain for-loop for accumulation? How does functools.singledispatch enable function overloading based on argument type? What is functools.cached_property and how does it differ from @property combined with manual caching?
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How do you use functools.partial to fix keyword arguments for logging or callback functions?

Beginner

Answer

partial(func, **kwargs) pre-binds keyword arguments, returning a new callable that only needs the remaining arguments when invoked. This is a common pattern for adapting a general-purpose function to an event system or callback API that calls it with a fixed signature.
from functools import partial
import logging

def log(message, level='INFO'):
    print(f'[{level}] {message}')

warn = partial(log, level='WARNING')
warn('Disk space low')  # [WARNING] Disk space low
Real-world example A task scheduler registers partial(send_email, template='reminder') as the callback so the scheduler only needs to supply the recipient at call time.

Common follow-ups: Can partial objects be introspected to see bound arguments?;How does partial interact with **kwargs at call time?

Decorators;Closures
All 15 functools & Functional Programming Tools questions