input: Write a function to replace numbers divisible by 3 with 'Fizz' in a given range.
  assert fizz_buzz(1, 10) == [1, 2, 'Fizz', 4, 5, 'Fizz', 7, 8, 'Fizz', 10]
  assert fizz_buzz(15, 20) == ['Fizz', 16, 17, 'Fizz', 19, 20]
  assert fizz_buzz(1, 5) == [1, 2, 'Fizz', 4, 5]
output: def fizz_buzz(start, end):
      result = []
      for num in range(start, end + 1):
          if num % 3 == 0:
              result.append('Fizz')
          else:
              result.append(num)
      return result