出现了这个报错: Could not fetch URL https://pypi.python.org/simple/cryptography/: There was a problem confirming the ssl certificate: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:748) - skipping
一开始以为是fiddler开着的原因,因为fiddler会影响request的端口,后面发现不是这个原因。
后面用了这个命令: pip install --trusted-host pypi.python.org pip --upgrade
就解决了