@property
    def oauth(self):
        if self._oauth is None:
            raise XeroNotVerified("OAuth credentials haven't been verified")
        return self._oauth
Target database must support window functions.
dataset/ETHPy150Open freakboy3742/pyxero/xero/auth.py/PublicCredentials.oauth--crossover with--dataset/ETHPy150Open RoseOu/flasky/venv/lib/python2.7/site-packages/sqlalchemy/testing/requirements.py/SuiteRequirements.window_functions