diff --git a/app/covid-calculator.ipynb b/app/covid-calculator.ipynb
index f5746948..e0d61f35 100644
--- a/app/covid-calculator.ipynb
+++ b/app/covid-calculator.ipynb
@@ -8,7 +8,7 @@
    },
    "outputs": [],
    "source": [
-    ""
+    "import ipywidgets as widgets"
    ]
   }
  ],