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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 wait(self):
 """ Starts all greenlets for concurrent processing. Joins over all greenlets that are not servers. """

        for greenlet in (self.greenlets + self.servers):
            log.info("Starting {} greenlet...".format(greenlet))
            greenlet.start()

        gevent.joinall(self.greenlets)