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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 data_url(contents, domain=DEFAULT_DOMAIN):
 """ Return the URL for embedding the GeoJSON data in the URL hash Parameters contents - string of GeoJSON domain - string, default http://geojson.io """

    url = (domain + '#data=data:application/json,' +
           urllib.parse.quote(contents))
    return url