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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 collect(self):
 """ Collector Passenger stats """

        if not os.access(self.config["bin"], os.X_OK):
            self.log.error("Path %s does not exist or is not executable",
                           self.config["bin"])
            return {}

        dict_stats = self.get_passenger_memory_stats()
        if len(dict_stats.keys()) == 0:
            return {}

        queue_stats = self.get_passenger_queue_stats()
        if len(queue_stats.keys()) == 0:
            return {}

        overall_cpu = self.get_passenger_cpu_usage(dict_stats)
        if overall_cpu >= 0:
            self.publish("phusion_passenger_cpu", overall_cpu)

        self.publish("total_passenger_procs", len(
            dict_stats["passenger_procs"]))
        self.publish("total_nginx_procs", len(dict_stats["nginx_procs"]))
        self.publish("total_apache_procs", len(dict_stats["apache_procs"]))
        self.publish("total_apache_memory", dict_stats["apache_mem_total"])
        self.publish("total_nginx_memory", dict_stats["nginx_mem_total"])
        self.publish("total_passenger_memory",
                     dict_stats["passenger_mem_total"])
        self.publish("top_level_queue_size", queue_stats[
                     "top_level_queue_size"])
        self.publish("passenger_queue_size", queue_stats[
                     "passenger_queue_size"])