docs: public Integer getNodesPartitionIdForKey(int nodeId, final byte[] key) {
          // this is all the partitions the key replicates to.
          List<Integer> partitionIds = getReplicatingPartitionList(key);
          for(Integer partitionId: partitionIds) {
              // check which of the replicating partitions belongs to the node in
              // question
              if(getNodeIdForPartitionId(partitionId) == nodeId) {
                  return partitionId;
              }
          }
          return null;
      }