[Python] How to mock __next__ magic method?

How to mock Queue.__next__ magic method? The code below with side_effect is not working:

from unittest.mock import MagicMock


class Queue:

def __init__(self):
self.nums = [1, 2, 3]

def __iter__(self):
return self

def __next__(self):
try:
num = self.nums.pop()
except Exception:
raise StopIteration
return num


class Consumer:

def __init__(self, queue):
self._queue = queue

def consume(self):
for msg in self._queue:
raise ValueError(msg)


def test_it():
queue = MagicMock()
queue.__next__.side_effect = [4, 5, 6] # not working
consumer = Consumer(queue)
consumer.consume()


Python interpreter is not even going inside __next__ method. How to make it work?

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