How to Async Open File Dialog in Apex - Code Snippet

// Task: Async Open File Dialog
// Language: Apex

public void async_open_file_dialog() {
    // Implementation for Async Open File Dialog
    Object result = ...; // Initialize variable
    // TODO: Implement core logic here
    // Step 1: Prepare data
    // Step 2: Process Async Open File Dialog
    System.debug("Done");
}