我試圖返回一個由每個關鍵字以及每個關鍵字及其同義詞在每個文檔中出現的次數組成的元組列表。當輸入只是一個字符串（例如“happy”）時，我沒有問題，但是當我嘗試更多輸入（例如“happy”和“sad”）時，代碼只打印最后一個字符串的輸出（“sad”） ）這是我的代碼：class Entry :    def __init__(self, input_word, input_synonyms) :        self.word = input_word        self.synonyms = input_synonymse1 = Entry("sad", ["unhappy", "upset"])e2 = Entry("happy", ["cheerful", "joyful"])Thesaurus = [e1, e2]doc1 = ["the", "man", "is", "sad", "very", "sad", "and", "unhappy", "and", "upset"]doc2 = ["the", "boy", "is", "happy", "cheerful", "and", "joyful"]Corpus = [doc1, doc2]def search(keyword) :    all_words = [keyword]    for entry in Thesaurus:        if entry.word == keyword:            for word in entry.synonyms:                all_words.append(word)    store = []    for search_word in all_words:        count = 0        for document in Corpus:            for word in document:                if search_word == word:                    count = count + 1        store.append([search_word, count])    return storeinput_ = "happy" and "sad"output = search(input_)print(output)控制臺輸出：[['sad', 2], ['unhappy', 1], ['upset', 1]]預期輸出：[['happy', 1], ['cheerful', 1], ['joyful', 1], ['sad', 2], ['unhappy', 1], ['upset', 1]]有什么辦法可以解決這個問題嗎？