input: Write a function named `check_valid_shuffling` that takes a list of integers as input and returns `True` if it is possible to rearrange the list such that it becomes a valid 90-degree clockwise rotation of some array, and `False` otherwise. A valid 90-degree clockwise rotation means that the list can be split into four contiguous subarrays where the elements in each subarray are in strictly increasing order. If the input list is empty, return `True`.
  
  assert check_valid_shuffling([1, 2, 3, 4]) == True
  assert check_valid_shuffling([4, 3, 2, 1]) == True
  assert check_valid_shuffling([1, 3, 2, 4]) == True
  assert check_valid_shuffling([1, 2, 3, 4, 5]) == False
  assert check_valid_shuffling([]) == True
output: def check_valid_shuffling(lst):
      if not lst:
          return True
      n = len(lst)
      if n % 4 != 0:
          return False
      k = n // 4
      subarrays = [lst[i*k:(i+1)*k] for i in range(4)]
      for subarray in subarrays:
          if not all(subarray[i] < subarray[i+1] for i in range(len(subarray)-1)):
              return False
      return True