[Python] How can I test that a method of a class was passed as a parameter to a mocked method

Say I have classes like this:

class MyTask(QtCore.QObject):
def do(self):
...

class Manager(QtCore.QObject):
def __init__(self):
super().__init__()
self.worker_executor = concurrent.futures.ThreadPoolExecutor()

def run_task(self):
self.worker_executor.submit(MyTask().do)


I want to test, using pytest, that method do of an (i.e. any) instance of MyTask is passed as the parameter of ThreadPoolExecutor.submit.

manager.worker_executor.submit = mock.Mock()
manager.run_task()
mock_call = manager.worker_executor.submit.call_args_list[0]
assert mock_call.args[0] == myTask.do # False


I'm not surprised this fails, with a message like:

AssertionError: assert <bound method MyTask.do of <MyTask object at 0x000001B07E6537F0>> == <function MyTask.do at 0x000001B07D2E3BE0>


as a bound method is being compared with a function.

Equivalent to How to verify that specific class method was passed as parameter?, but that relates to Java and a Java mocking framework.

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