convert shebang lines: python -> python3
diff --git a/Tools/webchecker/webchecker.py b/Tools/webchecker/webchecker.py
index 651cf85..7c3124c 100755
--- a/Tools/webchecker/webchecker.py
+++ b/Tools/webchecker/webchecker.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # Original code by Guido van Rossum; extensive changes by Sam Bayer,
 # including code to check URL fragments.