How to use the comiccrawler.download_manager.download_manager function in comiccrawler

def beforequit():
			if download_manager.is_downloading():
				if not messagebox.askokcancel(
						"Comic Crawler",
						"任務下載中，確定結束？"):
					return
					
			# going to quit
			printer.remove_listener(self.sp_callback)		
		
			self.root.destroy()
			
			download_manager.stop_download()
			download_manager.stop_analyze()
			download_manager.stop_check_update()
			
			mission_manager.save()
			
			config.save()

def beforequit():
			if download_manager.is_downloading():
				if not messagebox.askokcancel(
						"Comic Crawler",
						"任務下載中，確定結束？"):
					return
					
			# going to quit
			printer.remove_listener(self.sp_callback)		
		
			self.root.destroy()
			
			download_manager.stop_download()
			download_manager.stop_analyze()
			download_manager.stop_check_update()
			
			mission_manager.save()
			
			config.save()

def beforequit():
			if download_manager.is_downloading():
				if not messagebox.askokcancel(
						"Comic Crawler",
						"任務下載中，確定結束？"):
					return
					
			# going to quit
			printer.remove_listener(self.sp_callback)		
		
			self.root.destroy()
			
			download_manager.stop_download()
			download_manager.stop_analyze()
			download_manager.stop_check_update()
			
			mission_manager.save()

def add_analyze(self, mission, on_success=None):
		def on_finished(err):
			if err and not isinstance(err, worker.WorkerExit):
				self.thread.later(
					self.messagebox,
					"error",
					mission.module.name,
					"解析錯誤！\n{}".format(err)
				)
			if not err and on_success:
				on_success()
		download_manager.start_analyze(mission, on_finished=on_finished)

self.pre_url = url
				if ask_analyze_update(mission):
					mission.state = 'ANALYZE_INIT'
					download_manager.start_analyze(mission)
				return
					
			try:
				mission = create_mission(url)
			except ModuleError:
				messagebox.showerror(
					"Comic Crawler",
					"建立任務失敗！不支援的網址！"
				)
			else:
				self.pre_url = url
				download_manager.start_analyze(mission)

self.create_view()
		
		self.pool_index = {
			id(mission_manager.view): self.view_table,
			id(mission_manager.library): self.library_table
		}
		
		self.bindevent()
		
		self.register_listeners()
		
		printer.add_listener(self.sp_callback)

		if (setting.getboolean("libraryautocheck") and
			time() - setting.getfloat("lastcheckupdate", 0) > 24 * 60 * 60):
			download_manager.start_check_update()
			
		self.update_table(mission_manager.view)
		self.update_table(mission_manager.library)
		
		self.save()
		self.update()
		self.root.mainloop()

def _():
					missions = table.selected()
					download_manager.start_check_update(missions)

def libCheckUpdate():
			download_manager.start_check_update()
		self.btn_update["command"] = libCheckUpdate

def lib_download_update():
			missions = mission_manager.get_all("library", lambda m: m.state == "UPDATE")
			if not missions:
				self.messagebox("error", "Comic Crawler", "沒有新更新的任務")
				return
			mission_manager.add("view", *missions)
			download_manager.start_download()
			self.notebook.select(0)
		self.btn_download_update["command"] = lib_download_update