title: PhotoKit - Swift 4 - How to find identical Photos or duplicate photos - PHFetchResult<PHAsset>
body: <p>I was able to get the list of photos from photo library with the following code.</p>
  
  <pre><code>  guard let assetCollection = collection as? PHAssetCollection
                  else { fatalError("asset collection is required.") }
              destination.fetchResult = PHAsset.fetchAssets(in: assetCollection, options: nil) 
  </code></pre>
  
  <p>destination.fetchResult gets all the Photos in terms of PHAssets.I want to f find duplicate photos present in PHFetchResult.</p>
  
  <p>Please suggest any advices.</p>