// UploadPostView.Swift
Button.sheet(isPresented, onDismiss, content)
Method to present modal view. This method waiting until @State variable for isPresented is changed. If modal was dismissed, execute the method for onDismiss.
Then the @State var is no longer nil, hit the else block, and we upwrap the selected image.
// UploadPost/UploadPostView.swift
@State private car selectedImage: UIImage?
Create a state variable in the parent view
// Utils/ImagePicker.swift
@Binding var image: UIImage?
Create a binding variable in the view that doing another stuff.

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