def test_negative_number(self):
     for i in range(-1, -10, -1):
         self.assertFalse(is_prime(i), msg="failed on {}".format(i))
 def test_is_four_non_prime(self):
     self.assertFalse(is_prime(4), msg="4 is not prime")
 def test_is_zero_not_prime(self):
     self.assertFalse(is_prime(0))
 def test_is_five_prime(self):
     self.assertTrue(is_prime(5))