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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 _add_query_parameters(base_url, name_value_pairs):
 """Add one query parameter to a base URL. :type base_url: string :param base_url: Base URL (may already contain query parameters) :type name_value_pairs: list of (string, string) tuples. :param name_value_pairs: Names and values of the query parameters to add :rtype: string :returns: URL with additional query strings appended. """

    if len(name_value_pairs) == 0:
        return base_url

    scheme, netloc, path, query, frag = urlsplit(base_url)
    query = parse_qsl(query)
    query.extend(name_value_pairs)
    return urlunsplit((scheme, netloc, path, urlencode(query), frag))