使用pip按照virtualenv报错，如下：
pip install djangorestframework Collecting djangorestframework Could not fetch URL https://pypi.python.org/simple/djangorestframework/: There was a problem confirming the ssl certificate: [SSL: CERTIFICATE_VERIFY_FAILED] certificate verify failed (_ssl.c:590) - skipping Could not find a version that satisfies the requirement djangorestframework(from versions: )
使用–trusted-host命令行选项
pip --trusted-host pypi.python.org install djangorestframeworkPython djangorestframework安装库报错SSL: CERTIFICATE_VERIFY_FAILED
原文：http://www.cnblogs.com/twyth/p/7204724.html