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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 is_meta_url (attr, attrs):
 """Check if the meta attributes contain a URL."""

    res = False
    if attr == "content":
        equiv = attrs.get_true('http-equiv', u'').lower()
        scheme = attrs.get_true('scheme', u'').lower()
        res = equiv in (u'refresh',) or scheme in (u'dcterms.uri',)
    if attr == "href":
        rel = attrs.get_true('rel', u'').lower()
        res = rel in (u'shortcut icon', u'icon')
    return res