A reference of the field variable is missing

If I just add the code on the sidebar the console says that the field variable is undefined, so I've included a reference with the variable in  the initial code block

site/content/tutorial/06-bindings/14-component-this/text.md

@@ -5,6 +5,10 @@ title: Binding to component instances
 Just as you can bind to DOM elements, you can bind to component instances themselves. For example, we can bind the instance of `<InputField>` to a prop named `field` in the same way we did when binding DOM Elements
 
 ```html
+<script>
+	let field;
+</script>
+
 <InputField bind:this={field} />
 ```
 
@@ -16,4 +20,4 @@ Now we can programmatically interact with this component using `field`.
 </button>
 ```
 
-> Note that we can't do `{field.focus}` since field is undefined when the button is first rendered and throws an error.
+> Note that we can't do `{field.focus}` since field is undefined when the button is first rendered and throws an error.