input: 
  import random
  
  def randomized_list(num_list):
      """ Randomizes the given list of integers using an optimized Fisher-Yates algorithm.
      >>> randomized_list([1, 2, 3, 4, 5])
      [3, 5, 1, 4, 2]
      >>> randomized_list([10, 20, 30])
      [20, 30, 10]
      """
      for i in range(len(num_list) - 1, 0, -1):
          j = random.randint(0, i)
          num_list[i], num_list[j] = num_list[j], num_list[i]
      return num_list
  
output:     for i in range(len(num_list) - 1, 0, -1):
          j = random.randint(0, i)
          num_list[i], num_list[j] = num_list[j], num_list[i]
      return num_list