WARNING: Retrying (Retry(total=4, connect=None, read=None, redirect=None, status=None)) after connection broken by ‘ProxyError(‘Cannot connect to proxy.’, NewConnectionError(’<pip._vendor.urllib3.connection.HTTPSConnection object at 0x7f8347ad5ae0>: Failed to establish a new connection: [Errno 111] 拒绝连接’))': /simple/opencv-contrib-python/

我搜了一下，发现解决这个问题的方案有些奇葩

应该先要试试 unset 吧，具体操作看图。