LotDate | Python Fiddle

class LotDate_validation:
    
    STATE=[]
    
    def __init__(self, award_decision_date, cancellation_date, estimated_start_date, estimated_completion_date, completion_date):
        self.estimated_start_date=estimated_start_date
        self.award_decision_date=award_decision_date
        self.cancellation_date=cancellation_date
        self.estimated_completion_date=estimated_completion_date
        self.completion_date=completion_date
        
        
    def Estimated_Start_Date_Estimated_Completion_Date(self):
        'validating if estimated_completion_date is later than the estimated_start_date'
        if self.estimated_completion_date is not None and self.estimated_completion_date > self.estimated_start_date:
            LotDate_validation.STATE=True
            return LotDate_validation.STATE
        else:
            
            LotDate_validation.STATE=False
            return LotDate_validation.STATE
        
        
    def Estimated_Start_Date_Award_Decision_Date(self):
        'validating if award_decision_date is earlier than the estimated_start_date'
        if self.award_decision_date is not None and self.award_decision_date < self.estimated_start_date:
            LotDate_validation.STATE=True
            return LotDate_validation.STATE
        else:
            LotDate_validation.STATE=False
            return LotDate_validation.STATE
        
    
    def Estimated_Start_Date_Completion_Date(self):
        'validating if completion_date is later than the estimated_start_date'
        if self.completion_date is not None and self.completion_date > self.estimated_start_date:
            LotDate_validation.STATE=True
            return LotDate_validation.STATE
        else:
            LotDate_validation.STATE=False
            return LotDate_validation.STATE
    
    def Cancellation_Date_Award_Decision_Date(self):
        'validating if cancellation_date is later than or equal to award_decision_date'
        if self.cancellation_date is not None and self.award_decision_date is not None and self.cancellation_date >= self.award_decision_date:
            LotDate_validation.STATE=True
            return LotDate_validation.STATE
        else:
            LotDate_validation.STATE=False
            return LotDate_validation.STATE
        
        
# This is just for the sake of testing 
firstcontract=LotDate_validation('22-09-2009', None, '05-10-2009', '04-10-2010', '04-10-2010')
firstcontract.Cancellation_Date_Award_Decision_Date()

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