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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 process_once(self, timeout=0):
 """Process data from connections once. Arguments: timeout -- How long the select() call should wait if no data is available. This method should be called periodically to check and process incoming data, if there are any. If that seems boring, look at the process_forever method. """

        log.log(logging.DEBUG - 2, "process_once()")
        sockets = self.sockets
        if sockets:
            in_, out, err = select.select(sockets, [], [], timeout)
            self.process_data(in_)
        else:
            time.sleep(timeout)
        self.process_timeout()