code: def registIssue(self, CorpNum, cashbill, Memo, UserID=None):
          
          if cashbill == None:
              raise PopbillException(-99999999, "현금영수증 정보가 입력되지 않았습니다.")
  
          postData = ""
  
          if Memo != None or Memo != '':
              cashbill.memo = Memo
  
          postData = self._stringtify(cashbill)
  
          return self._httppost('/Cashbill', postData, CorpNum, UserID, "ISSUE")
docs: 현금영수증 즉시발행
              args
                  CorpNum : 팝빌회원 사업자번호
                  cashbill : 등록할 현금영수증 object. made with Cashbill(...)
                  UserID : 팝빌회원 아이디
              return
                  처리결과. consist of code and message
              raise
                  PopbillException