input: Write a python function to count the number of valid knight moves on a chessboard from a given position. 
  assert count_knight_moves(42) == 8
  assert count_knight_moves(11) == 2
  assert count_knight_moves(28) == 6
output: def count_knight_moves(position):
      moves = [
          (2, 1), (2, -1), (-2, 1), (-2, -1),
          (1, 2), (1, -2), (-1, 2), (-1, -2)
      ]
      row, col = divmod(position, 8)
      count = 0
      
      for dr, dc in moves:
          new_row, new_col = row + dr, col + dc
          if 0 <= new_row < 8 and 0 <= new_col < 8:
              count += 1
      
      return count