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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 urlencode_params(params):
 """URL encodes the parameters. :param params: The parameters :type params: list of key/value tuples. :rtype: string """

    # urlencode does not handle unicode strings in Python 2.
    # Firstly, normalize the values so they get encoded correctly.
    params = [(key, normalize_for_urlencode(val)) for key, val in params]
    # Secondly, unquote unreserved chars which are incorrectly quoted
    # by urllib.urlencode, causing invalid auth signatures. See GH #72
    # for more info.
    return requests.utils.unquote_unreserved(urlencode(params))