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Concurrency & performance

asyncio, threading, multiprocessing, and profiling-friendly performance patterns.

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Concurrency & performance medium

How to Use a Weakref Cache to Avoid Memory Leaks in Python

This code demonstrates building a value cache with weakref.WeakValueDictionary so objects can be garbage collected when no longer referenced, preventing memory leaks.

weakref caching memory
Python 
import weakref
import gc


class ExpensiveObject:
    def __init__(self, name):
        self.name = name

    def __repr__(self):
        return f"ExpensiveObject('{self.name}')"


class ObjectCache:
    def __init__(self):
        self._cache = weakref.WeakValueDictionary()

    def get_or_create(self, name):
       …
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