code: def p_xor_p_expression(tok):
          
          if len(tok) == 4:
              tok[0] = LogicalBinOpRule(tok[2], tok[1], tok[3])
          else:
              tok[0] = tok[1]
docs: xor_p_expression : and_p_expression OP_XOR_P xor_p_expression
                            | and_p_expression