python with open路径保存 只能保存到根目录 保存不到指定文件夹怎么回事？

python with open路径保存 把爬下来的图片下载hot_tv里 但是执行了只能保存到根目录 保存不到指定文件夹怎么回事
？

import requests
import csv

r_header = {
     'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/95.0.4638.69 Safari/537.36 Edg/95.0.1020.44'}
base_url = 'https://movie.douban.com/j/search_subjects'
r_paras = {'type': 'tv',
           'tag': '热门',
           'sort': 'recommend',
           'page_limit': 20,
           'page_start': 0}
rest = requests.get(base_url, headers=r_header, params=r_paras)
data = rest.json()
movies_dict = data['subjects']
movies_lst = []
for mv in movies_dict:
    title = mv['title']
    rate = mv['rate']
    img_url = mv['cover']
    movies_lst.append([title, rate, img_url])
    img = requests.get(img_url, headers=r_header)
    filename =img_url.split('/')[-1]
    print(filename)
    with open('D:/Py/tv_img' + str(filename), 'wb')as f:
         f.write(img.content)
with open('hot_tv.csv', 'a+', encoding='utf-8', newline='') as f:
    w = csv.writer(f)
    w.writerows(movies_lst)

写绝对路径试试，默认是当前路径吧