input: Write a function to take a list of integers as input and return a randomized version of the list using an optimized Fisher-Yates algorithm.
  def randomized_list(num_list):
      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
  
  assert randomized_list([1, 2, 3, 4]) != [1, 2, 3, 4]
  assert len(randomized_list([1, 2, 3, 4])) == 4
  assert randomized_list([]) == []
output: def randomized_list(num_list):
      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