All 15 Memory Management & Garbage Collection questions
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How does Python primarily manage memory for objects?

Beginner

Answer

CPython uses automatic reference counting as its primary memory management mechanism: every object tracks how many references point to it, and when that count drops to zero, the memory is immediately deallocated. A supplementary cyclic garbage collector handles reference cycles that reference counting alone cannot free.
import sys

a = [1, 2, 3]
print(sys.getrefcount(a))  # includes the temporary ref from getrefcount's own argument
b = a
print(sys.getrefcount(a))  # increased by one
Real-world example Understanding refcounting explains why a large object is freed the instant its last variable goes out of scope or is reassigned, without waiting for a garbage collection cycle.

Common follow-ups: What increases and decreases an object's reference count?;Why do reference cycles need a separate collector?

Memory Management & Garbage Collection;Data Types & Structures
All 15 Memory Management & Garbage Collection questions