code: def p_term(tok):
          
          if len(tok) == 4:
              tok[0] = MathBinOpRule(tok[2], tok[1], tok[3])
          else:
              tok[0] = tok[1]
docs: term : factor OP_PLUS term
                  | factor OP_MINUS term
                  | factor OP_TIMES term
                  | factor OP_DIVIDE term
                  | factor OP_MODULO term
                  | factor