执行sudo -H pip install numpy 报这个错

或 sudo pip install numpy

报：
/usr/local/lib/python2.7/dist-packages/pip/_vendor/requests/init.py:83: RequestsDependencyWarning: Old version of cryptography ([1, 2, 3]) may cause slowdown.
warnings.warn(warning, RequestsDependencyWarning)
The directory ‘/home/zzc/.cache/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 ‘/home/zzc/.cache/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: numpy in /usr/local/lib/python2.7/dist-packages (1.15.4)