from trac.web import clearsilverimport unittestdef suite():    try:        from doctest import DocTestSuite        return DocTestSuite(clearsilver)    except ImportError:        import sys        print>>sys.stderr, "WARNING: DocTestSuite required to run these tests"    return unittest.TestSuite()if __name__ == '__main__':    runner = unittest.TextTestRunner()    runner.run(suite())