input: Write a function to randomize a list of given integers using an optimized Fisher-Yates algorithm. The function should take a list of integers as input and return the randomized list. If the input list is empty, the function should return an empty list.
  
  assert randomized_list([1, 2, 3, 4, 5]) != [1, 2, 3, 4, 5]
  assert randomized_list([10, 20, 30]) != [10, 20, 30]
  assert randomized_list([]) == []
output: def randomized_list(lst):
      import random
      n = len(lst)
      for i in range(n - 1, 0, -1):
          j = random.randint(0, i)
          lst[i], lst[j] = lst[j], lst[i]
      return lst