assert( xml == """ <?xml version="1.0"?> <catalog> <book id="bk101" empty=""> <author>\(author)</author> <title>XML Developer's Guide</title> <genre>Computer</genre> <price>44.95</price> <publish_date>2000-10-01</publish_date> <description>An in-depth look at creating applications with XML.</description> </book> </catalog> """ )