def METHOD_NAME(self):
    data = [
        ((['Natasha', 'Steve', 'Tchalla', 'Wanda', 'Rocket'], 'Natasha'), 0),
        ((['Natasha', 'Steve', 'Tchalla', 'Wanda', 'Rocket'], 'Steve'), 1),
        ((['Natasha', 'Steve', 'Tchalla', 'Wanda', 'Rocket'], 'Rocket'), 4),
    ]
    error_message = 'The index of the friend to find is incorrect.'
    for variant, (params, result) in enumerate(data, start=1):
        with self.subTest(f'variation #{variant}', input=params, output=result):
            self.assertIs(find_my_friend(*params), result, msg=error_message)