Python升级后ssl模块不可用问题解决和浅析

在Cent0S 7.5下将Python 2.7.5升级到Python 3.6.6后，发现ssl模块不可用，具体详细信息如下所示：

 

[root@db-server ~]# pip list

Package    Version

---------- -------

pip        19.2.3 

setuptools 39.0.1 

WARNING: pip is configured with locations that require TLS/SSL, however the ssl module in Python is not available.

Could not fetch URL https://pypi.org/simple/pip/: There was a problem confirming the ssl certificate: HTTPSConnectionPool(host='pypi.org', port=443): Max retries exceeded with url: /simple/pip/ (Caused by SSLError("Can't connect to HTTPS URL because the SSL module is not available.",)) - skipping

[root@db-server ~]# python -V

Python 3.6.6

>>> import ssl

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

  File "/usr/local/lib/python3.6/ssl.py", line 101, in <module>

    import _ssl             # if we can't import it, let the error propagate

ModuleNotFoundError: No module named '_ssl'

>>> 

>>> import socket

>>> hasattr(socket,"SSL")

False

>>>