pip install （速度慢或者下载超时）使用豆瓣源

pip install xxx -i http://pypi.douban.com/simple/

如果如下报错

  The repository located at pypi.douban.com is not a trusted or secure host and is being ignored. If this repository is available via HTTPS we recommend you use HTTPS instead, otherwise you may silence this warning and allow it anyway with '--trusted-host pypi.douban.com'.
  Could not find a version that satisfies the requirement opencv-python (from versions: )
No matching distribution found for opencv-python
The repository located at pypi.douban.com is not a trusted or secure host and is being ignored. If this repository is available via HTTPS we recommend you use HTTPS instead, otherwise you may silence this warning and allow it anyway with '--trusted-host pypi.douban.com'.

改为pip install xxx -i http://pypi.douban.com/simple/ --trusted-host pypi.douban.com

来源：CSDN

作者：Rhythm_x

链接：https://blog.csdn.net/qq_28792801/article/details/81126625