code: private Session getOrCreateSession(@NotNull String keyspace) {
          Timer timer = getMetricsFactory().getTimer("cassandraClient.getOrCreateSession");
  
          Session currentSession = sessionsByKeyspace.computeIfAbsent(keyspace, key -> {
              LOGGER.debug("Create session for [{}]", keyspace);
  
              Session session = getCluster().connect(key);
              session.init();
  
              return session;
          });
  
          timer.stop();
  
          return currentSession;
      }
docs: Create session
  
  @param keyspace Default keyspace
  
  @return Session instance