input: Write a function to shuffle a list of numbers. If the input list is empty, return an empty list.
  
  import random
  
  def shuffle_list(nums):
      if not nums:
          return []
      random.shuffle(nums)
      return nums
  
  assert shuffle_list([1, 2, 3, 4, 5]) != [1, 2, 3, 4, 5]
  assert shuffle_list([]) == []
output: def shuffle_list(nums):
      if not nums:
          return []
      random.shuffle(nums)
      return nums