def clean(self):
if not self.priorDays and not self.startDate:<EOL><INDENT>raise ValidationError(_(<EOL>'<STR_LIT>' +<EOL>'<STR_LIT>'<EOL>))<EOL><DEDENT>super(GenericRepeatedExpense,self).clean()<EOL>
priorDays is required for Generic Repeated Expenses to avoid infinite loops