convert shebang lines: python -> python3
diff --git a/Lib/test/test_userstring.py b/Lib/test/test_userstring.py
index 0538138..7a8b932 100755
--- a/Lib/test/test_userstring.py
+++ b/Lib/test/test_userstring.py
@@ -1,4 +1,4 @@
-#!/usr/bin/env python
+#!/usr/bin/env python3
 # UserString is a wrapper around the native builtin string type.
 # UserString instances should behave similar to builtin string objects.