def is_valid(self):
        """
        Returns True if this subscription's status and period are current,
        false otherwise.
        """

        if not self.is_status_current():
            return False

        if not self.is_period_current():
            return False

        return True

        Returns True if this subscription's status and period are current,
        false otherwise.
        
djstripe/models/billing.py