import "github.com/urfave/cli" func main() { app := cli.NewApp() app.Usage = "My CLI Application" app.Flags = []cli.Flag { cli.GlobalStringFlag { Name: "myFlag", Usage: "My global string flag" } } app.Action = func(c *cli.Context) error { // Use the global string flag myFlagValue := c.GlobalString("myFlag") fmt.Println("My flag value is:", myFlagValue) return nil } err := app.Run(os.Args) if err != nil { fmt.Println(err) } }In this example, we define a new CLI application using the cli.NewApp() method. We then define a global string flag using the cli.GlobalStringFlag method and add it to the application using the app.Flags attribute. Finally, in the app.Action function, we retrieve the value of the global string flag using the c.GlobalString() method and print it to the console. Overall, the github.com/urfave/cli package is a useful library for building CLI applications in Go, and the Context structure with its GlobalString and other methods provide a way to store and retrieve variables throughout the application.