docs: public static String getZone(String[] availZones, InstanceInfo myInfo) {
          String instanceZone = ((availZones == null || availZones.length == 0) ? "default"
                  : availZones[0]);
          if (myInfo != null
                  && myInfo.getDataCenterInfo().getName() == DataCenterInfo.Name.Amazon) {
  
              String awsInstanceZone = ((AmazonInfo) myInfo.getDataCenterInfo())
                      .get(AmazonInfo.MetaDataKey.availabilityZone);
              if (awsInstanceZone != null) {
                  instanceZone = awsInstanceZone;
              }
  
          }
          return instanceZone;
      }