private static int showTimeZone(CliContext ctx, IoTDBConnection connection) {
    try {
      ctx.getPrinter().println("Current time zone: " + connection.getTimeZone());
    } catch (Exception e) {
      ctx.getPrinter().println("Cannot get time zone from server side because: " + e.getMessage());
      return CODE_ERROR;
    }
    return CODE_OK;
  }
If cli has not specified a zoneId, it will be set to cli's system timezone by default otherwise
for insert and query accuracy cli should set timezone the same for all sessions.

@param specialCmd
@param cmd
@param connection
@return execute result code
iotdb-client/cli/src/main/java/org/apache/iotdb/cli/AbstractCli.java