TenderDate | Python Fiddle

class TenderDate_validation:
    
    STATE=[]
    
    def __init__(self, cftpd, bid_deadline, canpd, pca_date):
        self.cftpd=cftpd
        self.bid_deadline=bid_deadline
        self.canpd=canpd
        self.pca_date=pca_date
       
        
    def Tender_Calling_Date_Contract_Award_Date(self):
        'validating if Contract_Award_Date (Schema ID: pca_date)  is later than the Tender_Calling_Date (Schema ID: cftpd)'
        if self.pca_date is not None and self.pca_date > self.cftpd:
            TenderDate_validation.STATE=True
            return TenderDate_validation.STATE
        else:
            TenderDate_validation.STATE=False
            return TenderDate_validation.STATE
            
            
    def Tender_Calling_Date_Bid_Deadline(self):
        'validating if Bid_Deadline (Schema ID: bid_deadline) is later than the Tender_Calling_Date'
        if self.bid_deadline is not None and self.bid_deadline > self.cftpd:
            TenderDate_validation.STATE=True
            return TenderDate_validation.STATE
        else:
            TenderDate_validation.STATE=False
            return TenderDate_validation.STATE
    
    
    def Tender_Calling_Date_Award_Notice_Date(self):
        'validating if Award_Notice_Date (Schema ID: canpd) is later than the Tender_Calling_Date'
        if self.canpd is not None and self.canpd > self.cftpd:
            TenderDate_validation.STATE=True
            return TenderDate_validation.STATE
        else:
            TenderDate_validation.STATE=False
            return TenderDate_validation.STATE
        
# This is just for the sake of testing        
firstcontract=TenderDate_validation('22-01-2009', '10-02-2009', '20-02-2009', '28-02-2009' )
firstcontract.Tender_Calling_Date_Contract_Award_Date()

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