1. change python2 rpms to python3 version.
2. update Cpython code to use new API in python3
Test:
Could pass rpm package build for fm-common
Story: 2007065
Task: 37942
Change-Id: Ie0490118bcc891c2e994b3eeb6efab24ac7951cb
Signed-off-by: Shuicheng Lin <shuicheng.lin@intel.com>
(cherry picked from commit a2af71b8675a9306a70bbd049d12c58570c9a3df)