下载https://pypi.python.org/pypi/Pillow/2.2.1#downloads
NOTE：
1.PIL and Pillow currently cannot co-exist in the same environment. If you want to use Pillow, please remove PIL first.
2. “import Image” to:“from PIL import Image”
3.If your code imports from _imaging, it will no longer work.
“ from PIL import Image
_imaging = Image.core”