Merge pull request #8139 from peterkh/devel

Fix "TypeError: group id must be integer" if groupid passed in for group key

library/system/user

@@ -440,7 +440,7 @@ class User(object):
     def group_exists(self,group):
         try:
             if group.isdigit():
-                if grp.getgrgid(group):
+                if grp.getgrgid(int(group)):
                     return True
             else:
                 if grp.getgrnam(group):