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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 placeFavicon(context):
 """ Gets Favicon-URL for the Model. Template Syntax: {% placeFavicon %} """

    fav = Favicon.objects.filter(isFavicon=True).first()
    if not fav:
        return mark_safe('<!-- no favicon -->')
    html = ''
    for rel in config:
        for size in sorted(config[rel], reverse=True):
            n = fav.get_favicon(size=size, rel=rel)
            html += '<link rel="%s" sizes="%sx%s" href="%s"/>' % (
                n.rel, n.size, n.size, n.faviconImage.url)

    default_fav = fav.get_favicon(size=32, rel='shortcut icon')
    html += '<link rel="%s" sizes="%sx%s" href="%s"/>' % (
        default_fav.rel, default_fav.size, default_fav.size, default_fav.faviconImage.url)

    return mark_safe(html)