将字典写入文本文件，并取出

ab={'lee':21,'liu':18,'ma':20,'gao':22}

#字典写入文件
def write_dict(d):
    with open('dict.txt','w') as file:
        file.write(json.dumps(d))

#字典从文件中读出
def read_dict():
    with open('dict.txt','r') as file:
        st=file.read()
    return json.loads(st)