How looks the CSV file?

I am very sorry, but i cannot find any information about the structure of the uploaded CSV file… I do not know, how the csv file has to look. When i upload any CSV file, the chart is empty. There is no information abut it https://github.com/madpixelslabs/visualizer/wiki/How-can-I-create-a-chart%3F Is there the example of the CSV file, which is working with this plugin, please?

https://wordpress.org/plugins/visualizer/