Photo Swipe, Add External Link to Images within .js file

Question

I'm new to PhotoSwipe, getting very confused about how to add an external link to image

this is the .js file I used to load images, however, it only has url and caption,

instance = PhotoSwipe.attach(
[
    { url: 'img/picture1.jpg', caption: 'Image 001'},
    { url: 'img/picture2.jpg', caption: 'Image 002'},
    { url: 'img/picture3.jpg', caption: 'Image 003'},
    { url: 'img/picture4.jpg', caption: 'Image 004'},
    { url: 'img/picture5.jpg', caption: 'Image 005'},
],
{
    target: window.document.querySelectorAll('#PhotoSwipeTarget')[0],
    preventHide: true,
    getImageSource: function(obj){
        return obj.url;
    },
    getImageCaption: function(obj){
        return obj.caption;
    }
}
);

other than doing this in html with

<ul id="Gallery">
<li><a href="images/full/01.jpg"><img src="images/thumb/01.jpg" alt="Image 01"      /></a></li>

</ul>

is there any other way to add a parameter within PhotoSwipe.attach to hyperlink the image with external link?