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Unwrapping with guard

Question 1/12: This code will print a message – true or false?

Hint: Click to show.

func double(number: Int?) -> Int? {
	guard let number = number else {
		return nil
	return number * 2
let input = 5
if let doubled = double(number: input) {
	print("\(input) doubled is \(doubled).")

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