I have a CentOS7 box here, so I just installed Chirp from the EPEL repository, and it fires up fine. The install pulled in pyserial and python-suds as dependencies.
=========================================================================================================================== Package Arch Version Repository Size =========================================================================================================================== Installing: chirp noarch 20190410-1.el7 epel 1.3 M Installing for dependencies: pyserial noarch 2.6-6.el7 base 124 k python-suds noarch 0.4.1-5.el7 base 204 k
Looking at the system here, I don't have a serial-0.9.97 anywhere in site packages, but it appears in your stacktrace. I suspect a only or conflicting version of that and/or pyserial.
mike, kj6vcp