I am following this lib's easiest node.js example that generates ppt: https://gitbrent.github.io/PptxGenJS/docs/quick-start/

I first tried in React.js, the writeFile() downloads a file so it works, but I don't understand how to do it in Node.js,

I expect that the writeFile() returns a file so I can send back to client, but it returns a string which is confusing. Any help is appreciated, thank you

Code

const createPowerPoint=async(req,res)=>{
// 1. Create a Presentation
let pres = new pptxgen();

// 2. Add a Slide to the presentation
let slide = pres.addSlide();

// 3. Add text to the Slide
slide.addText("Hello World");

// 4. Save the Presentation
let file = await pres.writeFile({ fileName: "Sample Presentation.pptx" });
res.json(file)

}

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