code: public java.util.List<PlacementGroup> getPlacementGroups() {
          if (placementGroups == null) {
              placementGroups = new com.amazonaws.internal.SdkInternalList<PlacementGroup>();
          }
          return placementGroups;
      }
docs: <p>
  Information about the placement groups.
  </p>
  
  @return Information about the placement groups.