Python 2与Python 3导入

Question

I have a script that is written in Python. The author decided to use new features only available in Python 3, so I had to update my version.

Now I am having trouble because the script crashes on an import statement, so I decided to do some debugging. I came to the conclusion that my Python 3 cannot import Image from PIL .

In Python 2:

Python 2.7.10 (default, Aug 22 2015, 20:33:39) 
[GCC 4.2.1 Compatible Apple LLVM 7.0.0 (clang-700.0.59.1)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from PIL import Image

Does not give an error, but in Python 3:

Python 3.5.0 (v3.5.0:374f501f4567, Sep 12 2015, 11:00:19) 
[GCC 4.2.1 (Apple Inc. build 5666) (dot 3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> from PIL import Image
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
ImportError: No module named 'PIL'

Why is this happening and how can I fix this?

Answer 1

PIL is not a standard library; you installed it for Python 2, but that installation is not (and cannot be) used by Python 3.

Install PIL (or rather, the Pillow fork) explicitly in Python 3 as well:

python3 -m ensurepip  # optional, makes sure pip is installed
python3 -m pip install Pillow