Permission denied when running "pip install"

Symptom

When attempting to install or upgrade packages using "pip install", you receive a permission denied error. 

For example: 

!pip install --upgrade scikit-learn

OSError: [Errno 13] Permission denied: '/usr/local/lib/python2.7/dist-packages/scikit-learn'

Solution

It's possible to install/upgrade packages in a workspace session, but you need to include the --user flag to avoid the permissions error.

For example:

!pip install --upgrade --user scikit-learn

However, this installation will not persist from run to run. If you consistently need this library upgrade, you have a couple of options:

• You can add scikit-learn==0.18.1 to your project's requirements.txt file, as outlined here. This will install it automatically at the start of every run.
• However, you may find that scikit-learn in particular is slow to install. So you may want to take advantage of compute environment caching.