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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:

def macaroon_ops(self, macaroons):
        ''' This method makes the oven satisfy the MacaroonOpStore protocol
        required by the Checker class.

        For macaroons minted with previous bakery versions, it always
        returns a single LoginOp operation.

        :param macaroons:
        :return:
        '''
        if len(macaroons) == 0:
            raise ValueError('no macaroons provided')

        storage_id, ops = _decode_macaroon_id(macaroons[0].identifier_bytes)
        root_key = self.root_keystore_for_ops(ops).get(storage_id)
        if root_key is None:
            raise VerificationError(
                'macaroon key not found in storage')
        v = Verifier()
        conditions = []

        def validator(condition):
            # Verify the macaroon's signature only. Don't check any of the
            # caveats yet but save them so that we can return them.
            conditions.append(condition)
            return True
        v.satisfy_general(validator)
        try:
            v.verify(macaroons[0], root_key, macaroons[1:])
        except Exception as exc:
            # Unfortunately pymacaroons doesn't control
            # the set of exceptions that can be raised here.
            # Possible candidates are:
            # pymacaroons.exceptions.MacaroonUnmetCaveatException
            # pymacaroons.exceptions.MacaroonInvalidSignatureException
            # ValueError
            # nacl.exceptions.CryptoError
            #
            # There may be others too, so just catch everything.
            raise six.raise_from(
                VerificationError('verification failed: {}'.format(str(exc))),
                exc,
            )

        if (self.ops_store is not None
            and len(ops) == 1
                and ops[0].entity.startswith('multi-')):
            # It's a multi-op entity, so retrieve the actual operations
            # it's associated with.
            ops = self.ops_store.get_ops(ops[0].entity)

        return ops, conditions