After updating python from Python-2.7.5 to be Python 2.7.14
Yum gave the following error:

yum update

There was a problem importing one of the Python modules
required to run yum. The error leading to this problem was:

No module named yum

Please install a package which provides this module, or
verify that the module is installed correctly.

It's possible that the above module doesn't match the
current version of Python, which is:
2.7.14 (default, Dec 20 2017, 14:47:38)
[GCC 4.8.3 20140911 (Red Hat 4.8.3-9)]

If you cannot solve this problem yourself, please go to
the yum faq at:
http://yum.baseurl.org/wiki/Faq