// create a new UiMessage instance ui := &packer.UiMessage{} // display a plain message ui.Say("Hello, world!") // display a message with formatting ui.Message("The value of %s is %d", "x", 42) // display an error message ui.Error("Oops, something went wrong!")In these examples, we create a new UiMessage instance and use its methods to display different types of messages. The `Say` method displays a plain message, while the `Message` method allows us to format the message with values. Finally, the `Error` method displays an error message with a special styling. Overall, UiMessage is a useful package for adding user-friendly messages to Packer.