resize image using pillow

resize.py

img_io = cStringIO.StringIO()
app = current_app._get_current_object()

try:
    #pil_img.thumbnail(tuple(size), Image.ANTIALIAS)
    #pil_img.save(img_io, 'PNG')
    #img_io.seek(0)

    resized_img = pil_img.resize(tuple(size), Image.ANTIALIAS)
    resized_img.save(img_io, 'PNG')
    img_io.seek(0)
    return img_io
except Exception as e:
    app.logger.info("thumbnail> %r" % e)
    return None