diff --git a/res/boot/boot_dump.py b/res/boot/boot_dump.py
index ce78bc01d1bc9237a59bb43c7cb0c52080164ef4..729cd1542339caf01ab2a5deae53714abbe55630 100644
--- a/res/boot/boot_dump.py
+++ b/res/boot/boot_dump.py
@@ -11,7 +11,7 @@ def print_buffer(filename):
     buffer = [str(byte) for byte in data]
     buffer_s = ", ".join(buffer)
 
-    print("[" + buffer_s + "]")
+    print("[%s]" % buffer_s)
 
 if __name__ == "__main__":
     if len(sys.argv) < 2: