convert shebang lines: python -> python3
diff --git a/Tools/scripts/treesync.py b/Tools/scripts/treesync.py
index 8643ee7..b2649c4 100755
--- a/Tools/scripts/treesync.py
+++ b/Tools/scripts/treesync.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 """Script to synchronize two source trees.