diff --git a/artiq/examples/master/device_db.py b/artiq/examples/master/device_db.py
index da3f55707..95ec6a482 100644
--- a/artiq/examples/master/device_db.py
+++ b/artiq/examples/master/device_db.py
@@ -124,7 +124,7 @@ device_db = {
         "class": "SPIMaster",
         "arguments": {"channel": 23}
     },
-    "spi_mmc": { 
+    "spi_mmc": {
         "type": "local",
         "module": "artiq.coredevice.spi",
         "class": "SPIMaster",