diff --git a/utils/raspberrypi/ctt/ctt_pretty_print_json.py b/utils/raspberrypi/ctt/ctt_pretty_print_json.py
index 703a23fe2..3de8c108f 100644
--- a/utils/raspberrypi/ctt/ctt_pretty_print_json.py
+++ b/utils/raspberrypi/ctt/ctt_pretty_print_json.py
@@ -89,4 +89,5 @@ if __name__ == '__main__':
 
     input_filename = sys.argv[1]
     with open(input_filename, "r") as fin:
-        pretty_print_json(fin.read(), "pretty.json")
+        printer = JSONPrettyPrinter(sys.stdout)
+        printer.print(fin.read())