if err != nil {
		panic(err)
	}
	return b
}

func returnRecursiveZip() (r io.ReaderAt, size int64) {
	b := rZipBytes()
	return bytes.NewReader(b), int64(len(b))
}

// biggestZipBytes returns the bytes of a zip file biggest.zip
// that contains a zip file bigger.zip that contains a zip file
// big.zip that contains big.file, which contains 2³²-1 zeros.