def test_returns_error_msg_if_value_is_negative(self):
     self.assertEquals(gen_prime_number(-10), 'Invalid input')
 def test_if_four_not_prime(self):
     self.assertNotIn(4, gen_prime_number(10))
 def test_it_works(self):
     self.assertEquals(gen_prime_number(10), [2, 3, 5, 7])
 def test_if_list(self):
     try:
         assert type(gen_prime_number(10)) is list
     except AssertionError:
         raise (AssertionError("Wrong type"))