Forbid any later GNU GPL versions autousage

diff --git a/pyimportcan.pl b/pyimportcan.pl
index 57f2c3f2912dac6e77477506220e4141be0758c9..b7a1ca541d9ee0493a02927d75a2a0f96da0ad75 100755 (executable)
--- a/pyimportcan.pl
+++ b/pyimportcan.pl
@@ -3,8 +3,7 @@
 # Copyright (C) 2013-2019 Sergey Matveev (stargrave@stargrave.org)
 # This program is free software: you can redistribute it and/or modify
 # it under the terms of the GNU General Public License as published by
-# the Free Software Foundation, either version 3 of the License, or
-# (at your option) any later version.
+# the Free Software Foundation, version 3 of the License.
 #
 # This program is distributed in the hope that it will be useful,
 # but WITHOUT ANY WARRANTY; without even the implied warranty of