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Write a function GetFizzBuzz that takes an integer n and returns:
"Fizz" if the number is divisible by 3"Buzz" if the number is divisible by 5"FizzBuzz" if the number is divisible by both 3 and 5GetFizzBuzz(3) → "Fizz"
GetFizzBuzz(5) → "Buzz"
GetFizzBuzz(15) → "FizzBuzz"
GetFizzBuzz(7) → "7"
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