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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 reverse_params(url_name, params=None, **kwargs):
 """ compute the reverse url of ``url_name`` and add to it parameters from ``params`` as querystring :param unicode url_name: a URL pattern name :param params: Some parameter to append to the reversed URL :type params: :obj:`dict` or :obj:`NoneType<types.NoneType>` :param **kwargs: additional parameters needed to compure the reverse URL :return: The computed reverse URL of ``url_name`` with possible querystring from ``params`` :rtype: unicode """

    url = reverse(url_name, **kwargs)
    params = urlencode(params if params else {})
    if params:
        return u"%s?%s" % (url, params)
    else:
        return url