In python I'm making a simulator program. I need to implement the "Fifo" , "lru", "Opt" and "Rand" algorthims. This is what I have so far if you can help me finish these algorithms.        def parse_input():        page_reference_string = input().split()        num_frames = int(input())        algorithms = []        while True:            try:                algorithm = input().strip()                algorithms.append(algorithm)            except:                break        return page_reference_string, num_frames, algorithms        def fifo(page_reference_string, num_frames):        # Implement FIFO algorithm here        pass        def lru(page_reference_string, num_frames):        # Implement LRU algorithm here        pass        def opt(page_reference_string, num_frames):        # Implement OPT algorithm here        pass        def rand(page_reference_string, num_frames):        # Implement RAND algorithm here        pass        def main():        page_reference_string, num_frames, algorithms = parse_input()            print("Page Reference String:", " ".join(page_reference_string))        print("Number of Frames:", num_frames)            for algorithm in algorithms:            if algorithm == "FIFO":                faults = fifo(page_reference_string, num_frames)            elif algorithm == "LRU":                faults = lru(page_reference_string, num_frames)            elif algorithm == "OPT":                faults = opt(page_reference_string, num_frames)            elif algorithm == "RAND":                faults = rand(page_reference_string, num_frames)            print(algorithm + ":", faults)        if __name__ == "__main__":        main()