Fixed syntax error on linux module from keyboard_handler

src/keyboard_handler/linux.py

@@ -21,7 +21,7 @@ def parse(s):
             lst.remove(item)
 #end if
     if len(lst) > 1: #more than one key, parse error
-        raise ValueError, 'unknown modifier %s' % lst[0]
+        raise ValueError('unknown modifier %s' % lst[0])
     return (m, lst[0].lower())
 class AtspiThread(threading.Thread):
     def run(self):