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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 scan(self):
 """Analyze state and queue tasks."""


        log.debug("scanning machine: %s..." % self.name)

        deployed = set()
        services = yield self.client.get_children(self.path + "/services")

        for name in services:
            log.debug("checking service: '%s'..." % name)

            try:
                value, metadata = yield self.client.get(
                    self.path + "/services/" + name + "/machines"
                    )
            except NoNodeException:
                log.warn(
                    "missing machines declaration for service: %s." %
                    name
                    )
                machines = []
            else:
                machines = json.loads(value)

            if machines:
                log.debug("machines: %s." % ", ".join(machines))

                if self.name in machines:
                    deployed.add(name)
            else:
                log.debug("service not configured for any machine.")

        count = len(deployed)
        log.debug("found %d service(s) configured for this machine." % count)

        running = yield self.client.get_children(
            self.path + "/machines/" + self.name
            )

        self.stopped = deployed - set(running)

        if self.stopped:
            log.debug("services not running: %s." % ", ".join(
                map(repr, self.stopped)))
        elif running:
            log.debug("all services are up.")