input: 
  def print_checkerboard(side_length: int) -> None:
      """Prints a checkerboard pattern of the given side length.
      >>> print_checkerboard(3)
      # #
       # 
      # #
      >>> print_checkerboard(2)
      # 
       #
      """
  
output:     for i in range(side_length):
          for j in range(side_length):
              if (i + j) % 2 == 0:
                  print("#", end=" ")
              else:
                  print(" ", end=" ")
          print()