CryptographyDeprecationWarning: Python 3.6 is no longer supported by the Python core team. Therefore

报错信息：

../.jumbo/lib/python3.6/site-packages/paramiko/transport.py:33
/home/tafdb/.jumbo/lib/python3.6/site-packages/paramiko/transport.py:33: CryptographyDeprecationWarning: Python 3.6 is no longer supported by the Python core team. Therefore, support for it is deprecated in cryptography and will be removed in a future release.
from cryptography.hazmat.backends import default_backend

../.jumbo/lib/python3.6/site-packages/paramiko/transport.py:219
/home/tafdb/.jumbo/lib/python3.6/site-packages/paramiko/transport.py:219: CryptographyDeprecationWarning: Blowfish has been deprecated
    "class": algorithms.Blowfish,

-- Docs: https://docs.pytest.org/en/stable/how-to/capture-warnings.html

加密不推荐警告：Python核心团队不再支持Python 3.6。因此，在密码学中不支持它。下一版本的密码学（40.0）将是最后一个支持Python 3.6的版本。

从cryptography.hazmat.backends导入default_backend

原因：

由于Python版本问题报错，此时版本python 3.6 ；cryptography-37.0.2

解决方案：

卸载，安装支持的版本

检查版本

pip show Cryptography

卸载

pip uninstall  cryptography

 安装较低版本

pip install  cryptography==3.3.1

运行代码，无报错