Create a function that takes a string as its argument and returns the string in reversed order.
reverse("Hello World") ➞ "dlroW olleH"
reverse("The quick brown fox.") ➞ ".xof nworb kciuq ehT"
reverse("Sample is really helpful!") ➞ "!lufpleh yllaer si elpmaS"
You can expect a valid string for all test cases.