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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 loadSessions(self, callback, bare_jid, device_ids):
 """ Return a dict containing the session for each device id. By default, this method calls loadSession for each device id. """


        if self.is_async:
            self.__loadSessionsAsync(callback, bare_jid, device_ids, {})
        else:
            return self.__loadSessionsSync(bare_jid, device_ids)