code: def next_instruction_in_row(self):
          
          index = self.index_in_row + 1
          if index >= len(self.row_instructions):
              return None
          return self.row_instructions[index]
docs: The instruction after this one or None.
  
          :return: the instruction in :attr:`row_instructions` after this or
            :obj:`None` if this is the last
          :rtype: knittingpattern.Instruction.InstructionInRow
  
          This can be used to traverse the instructions.
  
          .. seealso:: :attr:`previous_instruction_in_row`