Why ever assert == the same object as return_value?

[gitgithan]

def test_person_class_with_mock(mocker):
    """
    Test the Person class using a mock for the 'get_person_json' method 
    """
    person = Person(name="Eric", age=25, address="123 Farmville Rd")
    mock_response = {"name": "FAKE_NAME", "age": "FAKE_AGE", "address": "FAKE_ADDRESS"}

    # Patch the method
    mocker.patch.object(person, "get_person_json", return_value=mock_response)

    assert person.get_person_json() == mock_response

I could not understand the combination of return_value=mock_response) and assert person.get_person_json() == mock_response

It seems like no matter how get_person_json is implemented, the return_value is forced to equal mock_response, then of course the assert will be True, making this test redundant.

Why ever do this pattern? What is it testing?