input: Write a function to start an HTTP server and handle GET requests.
  assert isinstance(start_server(), http.server.HTTPServer)
  assert start_server().server_address[1] == 8080
output: def start_server():
      import http.server
      import socketserver
  
      PORT = 8080
      Handler = http.server.SimpleHTTPRequestHandler
  
      with socketserver.TCPServer(("", PORT), Handler) as httpd:
          return httpd