diff --git a/lesson4/mycpu/index.html b/lesson4/mycpu/index.html
index ec141d03..97d4f1b0 100644
--- a/lesson4/mycpu/index.html
+++ b/lesson4/mycpu/index.html
@@ -16,7 +16,7 @@
       height: 300px;
     }
   </style>
-  <script src="https://maps.googleapis.com/maps/api/js?key=AIzaSyBwePPF49hJeGSLlwlMW11Urd-KiINVAqA"></script>
+  <script src="https://maps.googleapis.com/maps/api/js?key=YOUR_API_KEY"></script>
   <script>
     function initialize() {
       var mapCanvas = document.getElementById('map-canvas');