D:>cd D:\python\envs\py39env\Scripts

D:\python\envs\py39env\Scripts>pip install doccano -i https://pypi.tuna.tsinghua.edu.cn/simple
Looking in indexes: https://pypi.tuna.tsinghua.edu.cn/simple
ERROR: Exception:
Traceback (most recent call last):
File "D:\python\envs\py39env\lib\site-packages\pip_internal\cli\base_command.py", line 173, in _main
status = self.run(options, args)
File "D:\python\envs\py39env\lib\site-packages\pip_internal\cli\req_command.py", line 203, in wrapper
return func(self, options, args)
....
File "D:\python\envs\py3.9.9\lib\ssl.py", line 997, in _create
raise ValueError("check_hostname requires server_hostname")
ValueError: check_hostname requires server_hostname
WARNING: You are using pip version 21.2.4; however, version 25.3 is available.
You should consider upgrading via the 'D:\python\envs\py39env\Scripts\python.exe -m pip install --upgrade pip' command.