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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 _send_xmpp_element(self, xmpp_element: XMPPElement):
 """ Serializes and sends the given XMPP element to kik servers :param xmpp_element: The XMPP element to send :return: The UUID of the element that was sent """

        while not self.connected:
            log.debug("[!] Waiting for connection.")
            time.sleep(0.1)

        self.loop.call_soon_threadsafe(self.connection.send_raw_data, (xmpp_element.serialize()))
        return xmpp_element.message_id