input: Write a function to determine if it is possible to get a list sorted in non-decreasing order by performing any number of right shift operations on the given list. For each right shift, the first element moves to the end of the list. If it is possible, return True; otherwise, return False. If the input list is empty, return True.
  assert right_shift_sortability([3, 4, 5, 1, 2])==True
  assert right_shift_sortability([3, 5, 10, 1, 2])==True
  assert right_shift_sortability([4, 3, 1, 2])==False
  assert right_shift_sortability([3, 5, 4, 1, 2])==False
  assert right_shift_sortability([])==True
output: def right_shift_sortability(lst):
      if not lst:
          return True
      n = len(lst)
      for i in range(n):
          if all(lst[j] <= lst[j + 1] for j in range(n - 1)):
              return True
          lst = lst[-1:] + lst[:-1]
      return False