diff --git a/docs/developer.md b/docs/developer.md
index 572d5f58b..9e23db656 100644
--- a/docs/developer.md
+++ b/docs/developer.md
@@ -378,7 +378,7 @@ from pathlib import Path
 
 exchange = ccxt.binance({
     'apiKey': '<apikey>',
-    'secret': '<secret>'
+    'secret': '<secret>',
     'options': {'defaultType': 'swap'}
     })
 _ = exchange.load_markets()