async def METHOD_NAME(self, session_type: str, session_id: str) -> JsonDict:
    """
    Retrieve data stored with create_session
    Args:
        session_type: The type for this session.
        session_id: The session ID returned from create_session.
    Raises:
        StoreError if the session cannot be found.
    """
    def _get_session(
        txn: LoggingTransaction, session_type: str, session_id: str, ts: int
    ) -> JsonDict:
        # This includes the expiry time since items are only periodically
        # deleted, not upon expiry.
        select_sql = """
        SELECT value FROM sessions WHERE
        session_type = ? AND session_id = ? AND expiry_time_ms > ?
        """
        txn.execute(select_sql, [session_type, session_id, ts])
        row = txn.fetchone()
        if not row:
            raise StoreError(404, "No session")
        return db_to_json(row[0])
    return await self.db_pool.runInteraction(
        "get_session",
        _get_session,
        session_type,
        session_id,
        self._clock.time_msec(),
    )