import unittest
import os
import platform

class Tests(unittest.TestCase):
    def test_0(self):
        self.assertTrue(True)

    @unittest.skip('skipped test')
    def test_1(self):
        self.fail("should have failed!")

    @unittest.skipIf(os.name=='posix', 'Not supported on Unix')
    def test_2(self):
        import winreg

    @unittest.skipUnless(platform.system() == 'Darwin', 'Mac specific test')
    def test_3(self):
        self.assertTrue(True)

    @unittest.expectedFailure
    def test_4(self):
        self.assertEqual(2+2, 5)

if __name__ == '__main__':
    unittest.main(verbosity=2)