项目场景：
学习神经网络，pip安装Tensorboard遇到超时问题
问题描述
使用Pip安装Tensorboard过程中遇到超时导致安装失败，日志警告和报错如下
WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ReadTimeoutError("HTTPSConnectionPool(host='files.pythonhosted.org',port=443): Read timed out. (read timeout=15)")': /packages/7f/3f/e84a3a8f81a1c19821ef618573ba13bc78a5a6da11bc2601159998baa9c5/grpcio-1.50.0-cp38-cp38-win_amd64.whl WARNING: Retrying (Retry(total=3, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ConnectTimeoutError(, 'Connection to files.pythonhosted.org timed out. (connect timeout=15)')': /packages/7f/3f/e84a3a8f81a1c19821ef618573ba13bc78a5a6da11bc2601159998baa9c5/grpcio-1.50.0-cp38-cp38-win_amd64.whl WARNING: Retrying (Retry(total=2, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ConnectTimeoutError(, 'Connection to files.pythonhosted.org timed out. (connect timeout=15)')': /packages/7f/3f/e84a3a8f81a1c19821ef618573ba13bc78a5a6da11bc2601159998baa9c5/grpcio-1.50.0-cp38-cp38-win_amd64.whl WARNING: Retrying (Retry(total=1, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ConnectTimeoutError(, 'Connection to files.pythonhosted.org timed out. (connect timeout=15)')': /packages/7f/3f/e84a3a8f81a1c19821ef618573ba13bc78a5a6da11bc2601159998baa9c5/grpcio-1.50.0-cp38-cp38-win_amd64.whl WARNING: Retrying (Retry(total=0, connect=None, read=None, redirect=None, status=None)) after connection broken by 'ConnectTimeoutError(, 'Connection to files.pythonhosted.org timed out. (connect timeout=15)')': /packages/7f/3f/e84a3a8f81a1c19821ef618573ba13bc78a5a6da11bc2601159998baa9c5/grpcio-1.50.0-cp38-cp38-win_amd64.whlERROR: Could not install packages due to an OSError: HTTPSConnectionPool(host='files.pythonhosted.org', port=443): Max retries exceeded with url: /packages/7f/3f/e84a3a8f81a1c19821ef618573ba13bc78a5a6da11bc2601159998baa9c5/grpcio-1.50.0-cp38-cp38-win_amd64.whl (Caused by ConnectTimeoutError(, 'Connection to files.pythonhosted.org timed out. (connect timeout=15)')) 原因分析：
其实就是找第三方库的时候链接超时，总是获取不到。自带的pip命令去国外的服务器请求第三方包了，所以超时，因而换成国内镜像下载即可，并且要信任镜像的URL主站。
解决方案：
这里给出换阿里源的解决方案，并信任主站
pip3 install [你要安装的包] -i http://mirrors.aliyun.com/pypi/simple/ --trusted-host mirrors.aliyun.com
最后安装成功
