pip install opencv-python报错:Read timed out.

报错内容如:
File “c:\users\1147\appdata\local\programs\python\python37\lib\site-packages\pip_vendor\urllib3\response.py”, line 365, in _error_catcher
raise ReadTimeoutError(self._pool, None, ‘Read timed out.’)
pip._vendor.urllib3.exceptions.ReadTimeoutError: HTTPSConnectionPool(host=‘files.pythonhosted.org’, port=443): Read timed out.
等
主要是网络的问题。
解决措施，使用以下命令即可:

pip install --default-timeout=1000 --ignore-installed opencv-python -i https://pypi.mirrors.ustc.edu.cn/simple/