今天安装一下requests模块，遇到网络问题
pip install requests
Retrying (Retry(total=4, connect=None, read=None, redirect=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', NewConnectionError('<pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x00000000044CF7B8>: Failed to establish a new connection: [Errno 10061] ',))': /simple/requests/ Retrying (Retry(total=3, connect=None, read=None, redirect=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', NewConnectionError('<pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x00000000044CF6A0>: Failed to establish a new connection: [Errno 10061] ',))': /simple/requests/ Retrying (Retry(total=2, connect=None, read=None, redirect=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', NewConnectionError('<pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x00000000044CF5F8>: Failed to establish a new connection: [Errno 10061] ',))': /simple/requests/ Retrying (Retry(total=1, connect=None, read=None, redirect=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', NewConnectionError('<pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x00000000044CF4A8>: Failed to establish a new connection: [Errno 10061] ',))': /simple/requests/ Retrying (Retry(total=0, connect=None, read=None, redirect=None)) after connection broken by 'ProxyError('Cannot connect to proxy.', NewConnectionError('<pip._vendor.requests.packages.urllib3.connection.VerifiedHTTPSConnection object at 0x00000000044CF358>: Failed to establish a new connection: [Errno 10061] ',))': /simple/requests/ Could not find a version that satisfies the requirement requests (from versions: ) No matching distribution found for requests
刚开始怀疑官方源不行，但是指定 阿里的源 并且给 trust-hosts 参数仍然不行，最后怀疑可能是代理造成的影响
可是查了任务管理器，并没有什么代理软件，然后觉得应该是之前代理软件起了系统代理的作用，尽管没运行，但是配置影响了整个系统
所以重新打开代理软件，把全局模式关闭了，然后就成功了