实现简单的搜索引擎＜1＞

class SearchEngineBase(object):
    def __init__(self):
        pass

    def add_corpus(self, file_path):
        with open(file_path, 'r') as fin:
            text = fin.read()
        self.process_corpus(file_path, text)

    def process_corpus(self, id, text):
        raise Exception('process_corpus not implemented.')

    def search(self, query):
        raise Exception('search not implemented.')

def main(search_engine):
    for file_path in ['1.txt', '2.txt', '3.txt', '4.txt', '5.txt']:
	     ###将文件逐个传递给add_corpus, 再传递给process_corpus函数
        search_engine.add_corpus(file_path)

    while True:
        query = input()
        results = search_engine.search(query)
        print('found {} result(s):'.format(len(results)))
        for result in results:
            print(result)
			
			

##SimpleEngine 类继承了SearchEngineBase
class SimpleEngine(SearchEngineBase):
    def __init__(self):
        super(SimpleEngine, self).__init__()
        self.__id_to_texts = {}

    def