Trying to make duplicates with permissions

Question

I am currently working on trying to make duplicates with permissions using google spreadsheet. There was a link that I saw that explained how to approach this(Google Sheet Duplicate with Permission). I used scenario 2 in which it explains the permission for it. The code below is what the responder came up with and is something that I want to implement for the situation that I am trying to work on.

function duplicateSheetWithProtections() {
    var ss = SpreadsheetApp.getActiveSpreadsheet(); 
    sheet = ss.getSheetByName('Template');
    sheet2 = sheet.copyTo(ss).setName('My Copy'); 
    var protections = sheet.getProtections(SpreadsheetApp.ProtectionType.RANGE);
    for (var i = 0; i < protections.length; i++) {
        var p = protections[i];
        var rangeNotation = p.getRange().getA1Notation();
        var p2 = sheet2.getRange(rangeNotation).protect();
        p2.setDescription(p.getDescription());
        p2.setWarningOnly(p.isWarningOnly());
        if (!p.isWarningOnly()) {
            p2.removeEditors(p2.getEditors());
            p2.addEditors(p.getEditors());
           // p2.setDomainEdit(p.canDomainEdit()); //  only if using an Apps domain 
        } 
    }
} 

However, I am running into an issue where I get an error in line 4 from the response the user put in the link I have attached. In line 4 I get an error that says

TypeError: Cannot read property 'copyTo' of null (line 4, file "Code")

I have been trying to debug the problem, but I still not understanding why the problem still occurs. Would definitely like to know what I missed or did wrong.

Answer 1

The referred error message means that ss.getSheetByName('Template') in

sheet = ss.getSheetByName('Template');

returned null. This occurred because your spreadsheet doesn't include a sheet named Template.