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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 change_display_name(self, first_name, last_name):
 """ Changes the display name :param first_name: The first name :param last_name: The last name """

        log.info("[+] Changing the display name to '{} {}'".format(first_name, last_name))
        return self._send_xmpp_element(account.ChangeNameRequest(first_name, last_name))