Cannot copy image and save with modified metadata

I would like to be able to select a photo in iOS using Swift from the Photos library using UIImagePicker and copy all the image (with modified Exif metadata) to a new photo which I save in Photos. If I use UIActivityViewController to choose the save option (from copy/save/assign to contact/print/add to shared album/save to file), the input image Exif metadata is not transferred when I create a new UIimage from the loaded image data with the modified metadata. How can get the image with modified Exif metadata attached to the saved photo?

Cannot copy image and save with modified metadata
 
 
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