def __repr__(self):
        return "<NamedRequirements({}{})>".format(
            self.name,
            ", filename='{}'".format(self.filename.name) if self.filename
            else "")
def active_at_datetime(self, deadline):
        """Check whether the verification was active at a particular datetime.

        Arguments:
            deadline (datetime): The date at which the verification was active
                (created before and expiration datetime is after today).

        Returns:
            bool

        """
        return (
            self.created_at < deadline and
            self.expiration_datetime > now()
        )