diff --git a/cts/cts-lab.in b/cts/cts-lab.in
index c204077f94..a0b2be576f 100644
--- a/cts/cts-lab.in
+++ b/cts/cts-lab.in
@@ -1,129 +1,129 @@
 #!@PYTHON@
 """ Command-line interface to Pacemaker's Cluster Test Suite (CTS)
 """
 
 __copyright__ = "Copyright 2001-2023 the Pacemaker project contributors"
 __license__ = "GNU General Public License version 2 or later (GPLv2+) WITHOUT ANY WARRANTY"
 
 import signal
 import sys
 
 from pacemaker._cts.CTS import CtsLab
 from pacemaker._cts.cmcorosync import Corosync2
 from pacemaker._cts.audits import audit_list
 from pacemaker._cts.logging import LogFactory
 from pacemaker._cts.scenarios import AllOnce, Boot, BootCluster, LeaveBooted, RandomTests, Sequence
 from pacemaker._cts.tests import test_list
 
 # These are globals so they can be used by the signal handler.
 scenario = None
 LogFactory().add_stderr()
 
 
 def sig_handler(signum, frame) :
-    LogFactory().log("Interrupted by signal %d"%signum)
+    LogFactory().log("Interrupted by signal %d" % signum)
 
     if scenario:
         scenario.summarize()
 
     if signum == 15:
         if scenario:
             scenario.teardown()
 
         sys.exit(1)
 
 
 def plural_s(n, uppercase=False):
     if n == 1:
         return ""
 
     if uppercase:
         return "S"
 
     return "s"
 
 
 if __name__ == '__main__':
 
     environment = CtsLab(sys.argv[1:])
     iters = environment["iterations"]
     tests = []
 
     # Set the signal handler
     signal.signal(15, sig_handler)
     signal.signal(10, sig_handler)
 
     # Create the Cluster Manager object
     cm = None
     if environment["Stack"] == "corosync 2+":
         cm = Corosync2()
 
     else:
-        LogFactory().log("Unknown stack: "+environment["stack"])
+        LogFactory().log("Unknown stack: %s" % environment["stack"])
         sys.exit(1)
 
     if environment["TruncateLog"]:
         if environment["OutputFile"] is None:
             LogFactory().log("Ignoring truncate request because no output file specified")
         else:
             LogFactory().log("Truncating %s" % environment["OutputFile"])
             with open(environment["OutputFile"], "w") as outputfile:
                 outputfile.truncate(0)
 
     audits = audit_list(cm)
 
     if environment["Listtests"]:
         tests = test_list(cm, audits)
-        LogFactory().log("Total %d tests"%len(tests))
+        LogFactory().log("Total %d tests" % len(tests))
         for test in tests :
-            LogFactory().log(str(test.name))
+            LogFactory().log(test.name)
         sys.exit(0)
 
     elif len(environment["tests"]) == 0:
         tests = test_list(cm, audits)
 
     else:
         chosen = environment["tests"]
         for test_case in chosen:
             match = None
 
             for test in test_list(cm, audits):
                 if test.name == test_case:
                     match = test
 
             if not match:
                 LogFactory().log("--choose: No applicable/valid tests chosen")
                 sys.exit(1)
             else:
                 tests.append(match)
 
     # Scenario selection
     if environment["scenario"] == "all-once":
         iters = len(tests)
         scenario = AllOnce(
             cm, [ BootCluster(cm, environment) ], audits, tests)
     elif environment["scenario"] == "sequence":
         scenario = Sequence(
             cm, [ BootCluster(cm, environment) ], audits, tests)
     elif environment["scenario"] == "boot":
         scenario = Boot(cm, [ LeaveBooted(cm, environment)], audits, [])
     else:
         scenario = RandomTests(
             cm, [ BootCluster(cm, environment) ], audits, tests)
 
-    LogFactory().log(">>>>>>>>>>>>>>>> BEGINNING " + repr(iters) + " TEST" + plural_s(iters, True) + " ")
+    LogFactory().log(">>>>>>>>>>>>>>>> BEGINNING %r TEST%s" % (iters, plural_s(iters, True)))
     LogFactory().log("Stack:                  %s (%s)" % (environment["Stack"], environment["Name"]))
     LogFactory().log("Schema:                 %s" % environment["Schema"])
     LogFactory().log("Scenario:               %s" % scenario.__doc__)
     LogFactory().log("CTS Exerciser:          %s" % environment["cts-exerciser"])
     LogFactory().log("CTS Logfile:            %s" % environment["OutputFile"])
     LogFactory().log("Random Seed:            %s" % environment["RandSeed"])
     LogFactory().log("Syslog variant:         %s" % environment["syslogd"].strip())
     LogFactory().log("System log files:       %s" % environment["LogFileName"])
     if "IPBase" in environment:
         LogFactory().log("Base IP for resources:  %s" % environment["IPBase"])
     LogFactory().log("Cluster starts at boot: %d" % environment["at-boot"])
 
     environment.dump()
     rc = environment.run(scenario, iters)
     sys.exit(rc)