Creating pdfs programmatically

Hello team,

I need to create the PDF after an order is placed and save that PDF to the google drive automatically.

I have checked your documentation to use the API for creating PDF programmatically but when I use this it is giving me below error:
Fatal error: Uncaught Error: Call to undefined function WPDFIB()

Please check this link where I have got the documentation: https://wooinvoice.rednao.com/knowledge-base/creating-pdfs-programmatically/

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