A simple After Effects script that creates a 3D camera, creates a null objects for the dolly, parents the camera to the dolly, and adds a wiggle expression to the null object. I wrote this when I was working on some projects that required me to do this every time I made a new comp. You can tell I was tired when I came up with the name.

HelloDolly01.jsx

{
    //Begins the undo group.
    app.beginUndoGroup("Add Camera and Dolly");
    
    //Creates a variable that holds the selected comp
    var curItem = app.project.activeItem;
    
    //Makes sure that there is an active comp
    if (curItem === null || !(curItem instanceof CompItem))
    {
        alert ("Please establish a comp as the active item and run the script again.");
    }
    else
    {
        //Getting the middle of the comp
        var compWidthMiddle = curItem.width / 2;
        var compHeightMiddle = curItem.height / 2;
        
        //Creating the camera
        var newCamera = curItem.layers.addCamera("3d camera 001",[compWidthMiddle,compHeightMiddle]);
        
        //Positioning the camera properly
        newCamera.property("position").setValue([compWidthMiddle,compHeightMiddle,-995.6]);
        newCamera.property("zoom").setValue(995.6);

        //Creating new null object
        var newDolly = curItem.layers.addNull(curItem.duration);
        
        //Add wiggle expression to null
        var wiggleExp = "seedRandom(time*.2); wiggle(1,5); //1=frequency 5=magnitude";
        newDolly.property("position").expression = wiggleExp;
        
        //Set the Null as the parent of the Camera
        newCamera.parent = newDolly;
    }
    app.endUndoGroup();
    
}