ptr:py3 apple$ sudo pip3 install Pillow

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: Pillow in /usr/local/lib/python3.6/site-packages

Requirement already satisfied: olefile in /usr/local/lib/python3.6/site-packages (from Pillow)

ptr:py3 apple$ python3

Python 3.6.2 (v3.6.2:5fd33b5926, Jul 16 2017, 20:11:06) 

[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin

Type "help", "copyright", "credits" or "license" for more information.

>>> from Pillow import Image

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

ModuleNotFoundError: No module named 'Pillow'

>>> from Pil import Image

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

ModuleNotFoundError: No module named 'Pil'

>>> from PIL import Image

Traceback (most recent call last):

  File "<stdin>", line 1, in <module>

ModuleNotFoundError: No module named 'PIL'