How to use the @node-minify/utils.utils.getFilesizeGzippedInBytes function in @node-minify/utils

.then(() => {
        utils
          .getFilesizeGzippedInBytes(options.output)
          .then(sizeGzip => {
            resolve({
              compressorLabel: options.compressorLabel,
              compressor: options.compressor,
              size: utils.getFilesizeInBytes(options.output),
              sizeGzip: sizeGzip
            });
          })
          .catch(reject);
      })
      .catch(reject);