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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_pass(self, new_pass):
 """ Change the client password for 'new_pass'. :param new_pass: New password of the client. :type new_pass: :class:`str` :param old_pass: Old password of the client. :type old_pass: :class:`str` """

        iq = aioxmpp.IQ(
            to=self.client.local_jid.bare().replace(localpart=None),
            type_=aioxmpp.IQType.SET,
            payload=xso.Query(self.client.local_jid.localpart, new_pass)
        )

        yield from self.client.send(iq)