读取txt文件用同义词替换的代码

以下是一个使用Python将txt文件中的指定单词替换为同义词的示例代码：

import nltk
from nltk.corpus import wordnet

# 读取txt文件
with open('example.txt', 'r') as file:
    text = file.read()

# 定义想替换的单词和对应的同义词
replace_dict = {'happy': 'joyful', 'sad': 'unhappy'}

# 对文本进行分词和词性标注
tokens = nltk.word_tokenize(text)
tokens_pos = nltk.pos_tag(tokens)

# 逐个检查每个单词是否需要替换
for i in range(len(tokens_pos)):
    word = tokens_pos[i][0]
    pos = tokens_pos[i][1]
    if word in replace_dict.keys() and pos.startswith('JJ'):  # 只替换形容词
        synonym_sets = wordnet.synsets(word, 'a')  # 获取单词的同义词集
        if synonym_sets:
            synonym = synonym_sets[0].lemmas()[0].name()  # 选择第一个同义词
            if synonym != word:
                tokens_pos[i] = (synonym, pos)  # 替换单词

# 将替换后的单词重新组成文本
new_text = ' '.join([token[0] for token in tokens_pos])

# 将文本写入新的txt文件中
with open('new_example.txt', 'w') as file:
    file.write(new_text)