input: Write a function that checks if a given list of integers can be sorted into non-decreasing order using any number of left shift operations. If it is possible, return True; otherwise, return False. If the given list is empty, return True.
  def left_shift_sortable(arr):
      if not arr:
          return True
      n = len(arr)
      for start in range(n):
          sorted_list = arr[:]
          for _ in range(n):
              if sorted(sorted_list) == sorted(arr):
                  return True
              sorted_list = [sorted_list[-1]] + sorted_list[:-1]
      return False
  assert left_shift_sortable([3, 4, 5, 1, 2])==True
  assert left_shift_sortable([3, 5, 10, 1, 2])==False
  assert left_shift_sortable([4, 3, 1, 2])==False
  assert left_shift_sortable([2, 3, 4, 1])==True
  assert left_shift_sortable([3, 5, 4, 1, 2])==False
  assert left_shift_sortable([])==True
output: def left_shift_sortable(arr):
      if not arr:
          return True
      n = len(arr)
      for start in range(n):
          sorted_list = arr[:]
          for _ in range(n):
              if sorted(sorted_list) == sorted(arr):
                  return True
              sorted_list = [sorted_list[-1]] + sorted_list[:-1]
      return False