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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 append_query_param(self, key, value):
 """ Append a query parameter :param string key: The query param key :param string value: The new value """

        values = self.query_param(key, as_list=True, default=[])
        values.append(value)
        return self.query_param(key, values)