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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 get_by_object(cls, pid_type, object_type, object_uuid):
 """Get a persistent identifier for a given object. :param pid_type: Persistent identifier type. :param object_type: The object type is a string that identify its type. :param object_uuid: The object UUID. :raises invenio_pidstore.errors.PIDDoesNotExistError: If no PID is found. :returns: A :class:`invenio_pidstore.models.PersistentIdentifier` instance. """

        try:
            return cls.query.filter_by(
                pid_type=pid_type,
                object_type=object_type,
                object_uuid=object_uuid
            ).one()
        except NoResultFound:
            raise PIDDoesNotExistError(pid_type, None)