convert shebang lines: python -> python3
diff --git a/Demo/sockets/gopher.py b/Demo/sockets/gopher.py
index c287319..bd29ec0 100755
--- a/Demo/sockets/gopher.py
+++ b/Demo/sockets/gopher.py
@@ -1,4 +1,4 @@
-#! /usr/bin/env python
+#! /usr/bin/env python3
 
 # A simple gopher client.
 #