diff --git a/test/pummel/test-child-process-spawn-loop.js b/test/pummel/test-child-process-spawn-loop.js
index f6d8207df85b9b..4dc218161125bf 100644
--- a/test/pummel/test-child-process-spawn-loop.js
+++ b/test/pummel/test-child-process-spawn-loop.js
@@ -30,7 +30,7 @@ const N = 40;
 let finished = false;
 
 function doSpawn(i) {
-  const child = spawn('python', ['-c', `print ${SIZE} * "C"`]);
+  const child = spawn('python', ['-c', `print(${SIZE} * "C")`]);
   let count = 0;
 
   child.stdout.setEncoding('ascii');