Exit when version is not supported

admin-tools/pyenv-newest-versions

@@ -5,4 +5,4 @@ if [[ $0 == ${BASH_SOURCE[0]} ]] ; then
     echo "This script should be *sourced* rather than run directly through bash"
     exit 1
 fi
-export PYVERSIONS='3.6.15 pypy3.6-7.3.1 3.7.16 pypy3.7-7.3.9 pypy3.8-7.3.10 pyston-2.3.5 3.8.16'
+export PYVERSIONS='3.6.15 pypy3.6-7.3.1 3.7.16 pypy3.7-7.3.9 pypy3.8-7.3.10 pyston-2.3.5 3.8.17'

uncompyle6/scanners/tok.py

@@ -94,6 +94,7 @@ class Token:
                 else:
                     if version_tuple > (3, 9):
                         print("Python versions 3.9 and greater are not supported.")
+                        sys.exit(1)
                     else:
                         print(f"xdis might need to be informed about version {e}")
                 return

uncompyle6/verify.py

@@ -1,5 +1,5 @@
 #
-# (C) Copyright 2015-2018, 2020-2021 by Rocky Bernstein
+# (C) Copyright 2015-2018, 2020-2021, 2023 by Rocky Bernstein
 # (C) Copyright 2000-2002 by hartmut Goebel <h.goebel@crazy-compilers.com>
 #
 #  This program is free software: you can redistribute it and/or modify