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import urllib, urlparse

def url_update_query(url, **kwargs):
    url_parts = list(urlparse.urlparse(url))
    query = dict(urlparse.parse_qsl(url_parts[4]))
    query.update(**kwargs)
    query = {k:v for (k,v) in query.items() if v}
    url_parts[4] = urllib.urlencode(query)
    final_url = urlparse.urlunparse(url_parts)
    return final_url