Uncaught ReferenceError: pdfjsLib is not defined

Question

I'm getting error Uncaught referenceError while trying to use jsPDF library

Here is my code snippets and I'm using jsPDF library version 2.0

    var myState = {
        pdf: null,
        currentPage: 1,
        zoom: 1
    }

    pdfjsLib.getDocument('/res/Pdf/164665736913e501e1e5bc3b6bb21707602ce363055efbcdaa6725e0216cce41ffc18c070b.pdf').then((pdf) => {
  
        myState.pdf = pdf;
        render();
    });
  }

  render() {
    myState.pdf.getPage(myState.currentPage).then((page) => {
        var canvas = document.getElementById("pdf_renderer");
        var ctx = canvas.getContext('2d');

        var viewport = page.getViewport(myState.zoom);

        canvas.width = viewport.width;
        canvas.height = viewport.height;
  
        page.render({
            canvasContext: ctx,
            viewport: viewport
        });
    }); 
  }
    
}```