boolean containsMember(InternalDistributedMember memberId) {
    if (nodes != null) {
      for (Node node : nodes) {
        if (memberId.equals(node.getMemberId())) {
          return true;
        }
      }
    }

    return false;
  }
Safely checks to see if the provided Node participates in the PartitionedRegion return true if
the Node participates in the PartitionedRegion
geode-core/src/main/java/org/apache/geode/internal/cache/PartitionRegionConfig.java