getAnchor(anchorId) {
        if (this.anchors[anchorId] === undefined) {
            this.anchors[anchorId] = new HassAnchor({type: HassAnchor.TYPE.ANCHOR, subType: anchorId});
        }

        return this.anchors[anchorId];
    }
Retrieve an instance for an anchor.

@public
@param {string} anchorId
@return {HassAnchor}