坑爹airflow，按着教程安装也全是坑
执行到airlfow initdb的时候报错，说找不到cryptography.fernet
然后安装了cryptography
结果又出了airflow.exceptions.AirflowException: Could not create Fernet object: Incorrect padding这个错
airflow.exceptions.AirflowExcept
来源：花图问答