function combineSourceMapChain (inputMapChain, original_code, filepath) {
    let mapGenerator, mapChain = prepareSourceMapChain(inputMapChain, original_code, filepath);

    if (mapChain.length > 1) {
        // @ts-ignore
        mapGenerator = SourceMap.SourceMapGenerator.fromSourceMap(new SourceMap.SourceMapConsumer(mapChain[0].map));

        for (let i = 1; i < mapChain.length; i++) {
            // @ts-ignore
            mapGenerator.applySourceMap(new SourceMap.SourceMapConsumer(mapChain[i].map), undefined, undefined);
        }
    } 

    return generateSourceMap(mapChain, mapGenerator, original_code, filepath);
}
@param {NollupTransformMapEntry[]} inputMapChain 
@param {string} original_code 
@param {string} filepath 
@return {RollupSourceMap}