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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_get_parameters(url, parameters, percent_encode=True):
 """Utility function to add GET parameters to an existing URL. Args: parameters A dictionary of the parameters that should be added. percent_encode Whether the query parameters should be percent encoded. Returns: The updated URL. """

    url_parts = list(parse.urlparse(url))
    query = dict(parse.parse_qs(url_parts[4]))
    query.update(parameters)

    if percent_encode:
        url_parts[4] = parse.urlencode(query)
    else:
        url_parts[4] = "&".join([key + "=" + value for key, value in query.items()])

    return parse.urlunparse(url_parts)