code: public RelationshipView getRelationshipView(@Nonnull Relationship relationship) {
          Optional<RelationshipView> relationshipView = this.relationshipViews.stream().filter(rv -> rv.getId().equals(relationship.getId())).findFirst();
          return relationshipView.orElse(null);
      }
docs: Gets the relationship view for the given relationship.
  
  @param relationship  the Relationship to find the RelationshipView for
  @return  an RelationshipView object, or null if the relationship doesn't exist in the view