code: protected Session getWriteSession() throws CpoException {
      Session session;
  
      try {
        session = getWriteDataSource().getSession();
      } catch (Throwable t) {
        String msg = "getWriteConnection(): failed";
        logger.error(msg, t);
        throw new CpoException(msg, t);
      }
  
      return session;
    }
docs: getWriteSession returns the write session for Cassandra
  
  @return A Session object for writing
  @throws CpoException