How does memory management work in Python?

Python automatically handles memory management, relieving developers of manual memory allocation and deallocation.

Reference Counting:

Every object keeps track of its reference count — the number of variables pointing to it. When the count reaches zero, the object is deleted:

import sys

a = [1, 2, 3]
print(sys.getrefcount(a))  # 2 (a + the function parameter itself)

b = a  # Another reference
print(sys.getrefcount(a))  # 3

del b  # Remove a reference
print(sys.getrefcount(a))  # 2

Garbage Collector:

Reference counting fails when there are circular references:

# Circular reference
a = []
b = []
a.append(b)
b.append(a)
del a, b
# The reference count won't reach zero, but the objects are unreachable

To solve this, Python runs a Garbage Collector (the gc module) that discovers and cleans up such cycles.

Key takeaways:

• Reference counting is the primary mechanism and runs immediately.
• Garbage collector is a secondary mechanism designed to break circular references.
• del removes a reference to an object, not necessarily the object itself.
• Developers rarely need to get involved in memory management — Python handles it perfectly.