input: Write a function to shuffle a list of numbers. The function should randomly rearrange the elements of the input list. If the input list is empty then return an empty list.
  assert shuffle_list([1, 2, 3, 4, 5])==[3, 4, 1, 5, 2]
  assert shuffle_list([10, 20, 30])==[30, 10, 20]
  assert shuffle_list([])==[]
  assert shuffle_list([1])==[1]
output: import random
  
  def shuffle_list(lst):
      if not lst:
          return []
      shuffled = lst[:]
      random.shuffle(shuffled)
      return shuffled