heat map Visualize doesn't work

[ChandrakalaRatan]

hi,

I am trying to display heat map visualization in reactjs. i copied the example given in the following website and trying to execute it. it doesn't throw any error, but it is not showing the points.

https://developers.arcgis.com/javascript/latest/sample-code/visualization-heatmap/index.html

https://codepen.io/pen?editors=1000

I downloaded cvs file and trying to load the file locally.

i also pasted the following link in my index.html too.

 <script src="https://js.arcgis.com/4.8/"></script>
        <link rel="stylesheet" href="https://js.arcgis.com/4.8/esri/css/main.css">
        <script src="https://js.arcgis.com/4.8/esri/views/2d/layers/BaseLayerViewGL2D.js"></script>
        <script src="https://js.arcgis.com/4.12/"></script>
        <link rel="stylesheet"  href="https://js.arcgis.com/4.12/esri/themes/light/main.css"/>

Please advise me what went wrong. i have attached my JS file with this email for your reference. please let me know any more information need.