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Detect Memory Leaks in Python with Weak References

A custom LeakDetector uses weak references and garbage collection to find class instances that survive past expected cleanup in long-running Python applications.

memory leak weakref

Python

import gc
import sys
import weakref
import time
from collections import defaultdict

class LeakDetector:
    def __init__(self):
        self._tracked = defaultdict(list)

    def track_class(self, cls):
        """Track all instances of a class for leak detection."""
        old_init = cls.__init__
        def new_in…

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