func fetchPHAssets() -> [PHAsset] {
   var assets = [PHAsset]()
   let options = PHFetchOptions.init()

   options.predicate = NSPredicate.init(format: "(mediaSubtype & %d) != 0", PHAssetMediaSubtype.photoScreenshot.rawValue)
    let fetchAssets: PHFetchResult = PHAsset.fetchAssets(with: .image, options: options)

 fetchAssets.enumerateObjects({ (asset, _, _) in
            assets.append(asset)
  })

  return assets
}

func fetchPHAssets() -> [PHAsset] {
        var assets = [PHAsset]()
        let options = PHFetchOptions.init()

        //retrieve only screen shots
        options.predicate = NSPredicate.init(format: "(mediaSubtype & %d) != 0", PHAssetMediaSubtype.photoScreenshot.rawValue)


        let fetchAssets: PHFetchResult = PHAsset.fetchAssets(in: PHAssetCollection.init(), options: nil)

        fetchAssets.enumerateObjects({ (asset, _, _) in
            assets.append(asset)
        })

        return assets
    }