gh-140025: Fix queue.SimpleQueue.__sizeof__() to account for buffer

[ayushm98]

Fixes #140025

Summary

The __sizeof__() method for queue.SimpleQueue now properly accounts for the dynamically allocated internal buffer.

Problem

Previously, SimpleQueue.__sizeof__() only returned the basic object size, ignoring the underlying RingBuf data structure that holds the queued items.

Solution

Implemented a custom __sizeof__() method that includes:

• Base object size
• Size of the dynamically allocated items array: items_cap * sizeof(PyObject*)

Example

import queue
q = queue.SimpleQueue()
initial_size = q.__sizeof__()

# Add many items to grow the buffer
for i in range(1000):
    q.put(i)

# Now __sizeof__() correctly reflects the larger buffer
larger_size = q.__sizeof__()
assert larger_size > initial_size

Changes

• Added simplequeue_sizeof() function in Modules/_queuemodule.c
• Added __sizeof__ to simplequeue_methods array

• Issue: queue.SimpleQueue.__sizeof__() ignores the underlying data structure #140025

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[python-cla-bot]

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• ayushkumarmalik10@gmail.com

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[picnixz]

There is already an open PR: #143137.