def test_release(self):
        """
        Test the release method.

        @raise AssertionError: If the test fails.
        """
        dog_pool = self.dog_pool_class()

        dog_one = dog_pool.acquire()
        dog_two = dog_pool.acquire()
        dog_two.sound = 'meow'

        dog_pool.release(dog_one)
        dog_three = dog_pool.acquire()
        self.assertEquals(id(dog_one), id(dog_three))

        dog_pool.release(dog_two)
        dog_four = dog_pool.acquire()
        self.assertEquals(id(dog_two), id(dog_four))

        self.assertEquals(dog_one.sound, dog_two.sound)
        self.assertEquals(dog_three.sound, dog_four.sound)
        self.assertEquals(dog_one.sound, dog_four.sound)

        Test the release method.

        @raise AssertionError: If the test fails.
        
tests/creational_tests/test_pool.py