def write_xspf(f, tuples):
    """send me a list of (artist,title,mp3_url)"""
    xml = XmlWriter(f, indentAmount='  ')
    xml.prolog()
    xml.start('playlist', { 'xmlns': 'http://xspf.org/ns/0/', 'version': '1' })
    xml.start('trackList')
    for tupe in tuples:
        xml.start('track')
        xml.elem('creator',tupe[0])
        xml.elem('title',tupe[1])
        xml.elem('location', tupe[2])
        xml.end()
    xml.end()
    xml.end()
    f.close()
send me a list of (artist,title,mp3_url)