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package main
import "fmt"

// `ToLower()` and `ToUpper()` functions are imported from the `strings` module
import "strings"

func capitalize(str string) string {
    return strings.ToUpper(str)
}

func operate(str string, operation ___) (string, string) {
    return str, operation(str)
}

func main() {
    inputString := "Hello World"
 
    var original string
    var updated string

    ___ = operate(___)
    fmt.Println(original, updated)
}