h := md5.New()
	_, err = io.Copy(h, gr)
	if err != nil {
		t.Fatalf("Expected GetObject reading data to succeed, but failed with %v", err)
	}
	gr.Close()

	const expectedHash = "fffb6377948ebea75ad2b8058e849ef5"
	foundHash := fmt.Sprintf("%x", h.Sum(nil))
	if foundHash != expectedHash {
		t.Fatalf("Expected data to have md5sum = `%s`, found `%s`", expectedHash, foundHash)
	}
}