load() {
        this.findIOHandler();
        if (this.handler.load == null) throw new Error("Cannot proceed with model loading because the IOHandler provided does not have the `load` method implemented.");
        const loadResult = this.handler.load();
        if ((0, _tfjsCore.util).isPromise(loadResult)) return loadResult.then((artifacts)=>{
            if (artifacts.getWeightStream == null) return this.loadSync(artifacts);
            return this.loadStreaming(artifacts);
        });
        return this.loadSync(loadResult);
    }
Loads the model and weight files, construct the in memory weight map and
compile the inference graph.