code: private void setRegionOrEndPoint() {
          String regionName = getParamString("ddb_region");
          if (regionName != null) {
              Regions regionEnum = Regions.fromName(regionName);
              Utils.require(regionEnum != null, "Unknown 'ddb_region': " + regionName);
              m_logger.info("Using region: {}", regionName);
              m_ddbClient.setRegion(Region.getRegion(regionEnum));
          } else {
              String ddbEndpoint = getParamString("ddb_endpoint");
              Utils.require(ddbEndpoint != null,
                            "Either 'ddb_region' or 'ddb_endpoint' must be defined for tenant: " + m_tenant.getName());
              m_logger.info("Using endpoint: {}", ddbEndpoint);
              m_ddbClient.setEndpoint(ddbEndpoint);
          }
      }
docs: Set the region or endpoint in m_ddbClient