def on_modified(self, event): new_name = "new_file"+ str(self.i) + ".txt" for filename in os.listdir(folder_to_track): file.exists= os.path.isfile(folder_destination + "/" + new_name) while file_exsist: self.i += 1 new_name = "new_file"+ str(self.i) + ".txt" file_exsist = os.pathisfile(folder_destination + "/" + new_name) src = folder_to_track + "/"+ filename new_destination = folder_destination + "/" + new_name os.rename(src, new_destination) folder_to_track = "\Users\Åmar\Desktop\myFolder" folder_destination = "\Users\Åmar\Desktop\myFolder" EventHandler = Myhandler() Observer=Observer() Observer.Schedule(Event_Handler, folder_to_track, recursive = True) Observer.start try: while True: time.sleep(10) except KeyboardInterrupt.