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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 get_payload(self):
 """ Return the query string of the uri. :return: the query string as a list """

        temp = self.get_uri_as_list()
        query_string = temp[4]
        if query_string == "":
            return None  # Bad request error code
        query_string_as_list = str.split(query_string, "=")
        return query_string_as_list[1]