convert shebang lines: python -> python3
diff --git a/Tools/webchecker/wcgui.py b/Tools/webchecker/wcgui.py
index 4ce613a..88d8f56 100755
--- a/Tools/webchecker/wcgui.py
+++ b/Tools/webchecker/wcgui.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 """GUI interface to webchecker.