How to install virtualenv by using pip in MacOS High Sierra?

Question

Command which i used to install virtualenv:-

sudo pip install virtualenv

Result:-

The directory '/Users/apple/Library/Caches/pip/http' or its parent directory is not owned by the current user and the cache has been disabled. Please check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.

The directory '/Users/apple/Library/Caches/pip' or its parent directory is not owned by the current user and caching wheels has been disabled. check the permissions and owner of that directory. If executing pip with sudo, you may want sudo's -H flag.

Requirement already satisfied: virtualenv in /Library/Frameworks/Python.framework/Versions/2.7/lib/python2.7/site-packages

Answer 1

sudo -H pip install virtualenv

（科德兰的字面意思不是foo ...）

Answer 2

如果尝试运行pip时要摆脱此错误，只需添加-H标志：

sudo -H pip install foo