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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_parameters(url, parameters):
 """ Appends URL-encoded parameters to the base URL. It appends after '&' if '?' is found in the URL; otherwise it appends using '?'. Keep in mind that this tag does not take into account the value of existing params; it is therefore possible to add another value for a pre-existing parameter. For example:: {% url 'this_view' as current_url %} {% with complete_url=current_url|add_parameters:request.GET %} The <a href="{% url 'other' %}?next={{ complete_url|urlencode }}"> other page</a> will redirect back to the current page (including any GET parameters). {% endwith %} """

    if parameters:
        sep = '&' if '?' in url else '?'
        return '{0}{1}{2}'.format(url, sep, urlencode(parameters))
    return url