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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def top_level_index_page(config):
 """HTML top-level index page which provides a link to each handler."""

    title = "IIIF Test Server on %s" % (config.host)
    body = "<ul>\n"
    for prefix in sorted(config.prefixes.keys()):
        body += '<li><a href="/%s">%s</a></li>\n' % (prefix, prefix)
    body += "</ul>\n"
    return html_page(title, body)