function createPDF(ssId, sheet, pdfName) {
  const fr = 0, fc = 0, lc = 9, lr = 27;
  const url = "https://docs.google.com/spreadsheets/d/" + ssId + "/export" +
    "?format=pdf&" +
    "size=7&" +
    "fzr=true&" +
    "portrait=true&" +
    "fitw=true&" +
    "gridlines=false&" +
    "printtitle=false&" +
    "top_margin=0.5&" +
    "bottom_margin=0.25&" +
    "left_margin=0.5&" +
    "right_margin=0.5&" +
    "sheetnames=false&" +
    "pagenum=UNDEFINED&" +
    "attachment=true&" +
    "gid=" + sheet.getSheetId() + '&' +
    "r1=" + fr + "&c1=" + fc + "&r2=" + lr + "&c2=" + lc;

  const params = { method: "GET", headers: { "authorization": "Bearer " + ScriptApp.getOAuthToken() } };
  const blob = UrlFetchApp.fetch(url, params).getBlob().setName(pdfName + '.pdf');

  // Gets the folder in Drive where the PDFs are stored.
  const folder = getFolderByName_(OUTPUT_FOLDER_NAME);

  const pdfFile = folder.createFile(blob);
  return pdfFile;
}
Creates a PDF for the customer given sheet.
@param {string} ssId - Id of the Google Spreadsheet
@param {object} sheet - Sheet to be converted as PDF
@param {string} pdfName - File name of the PDF being created
@return {file object} PDF file as a blob