Use context manager when opening images [ci skip]

docs/handbook/tutorial.rst

@@ -74,7 +74,8 @@ Convert files to JPEG
         outfile = f + ".jpg"
         if infile != outfile:
             try:
-                Image.open(infile).save(outfile)
+                with Image.open(infile) as im:
+                    im.save(outfile)
             except IOError:
                 print("cannot convert", infile)
 

docs/reference/ImageDraw.rst

@@ -20,7 +20,7 @@ Example: Draw a gray cross over an image
 
     from PIL import Image, ImageDraw
 
-    im = Image.open("hopper.jpg")
+    with Image.open("hopper.jpg") as im:
 
         draw = ImageDraw.Draw(im)
         draw.line((0, 0) + im.size, fill=128)

docs/reference/ImageSequence.rst

@@ -14,8 +14,7 @@ Extracting frames from an animation
 
     from PIL import Image, ImageSequence
 
-    im = Image.open("animation.fli")
-
+    with Image.open("animation.fli") as im:
         index = 1
         for frame in ImageSequence.Iterator(im):
             frame.save("frame%d.png" % index)

docs/reference/PixelAccess.rst

@@ -17,7 +17,7 @@ changes it.
 .. code-block:: python
 
     from PIL import Image
-    im = Image.open('hopper.jpg')
+    with Image.open('hopper.jpg') as im:
         px = im.load()
     print (px[4,4])
     px[4,4] = (0,0,0)

docs/reference/PyAccess.rst

@@ -18,7 +18,7 @@ The following script loads an image, accesses one pixel from it, then changes it
 .. code-block:: python
 
     from PIL import Image
-    im = Image.open('hopper.jpg')
+    with Image.open('hopper.jpg') as im:
         px = im.load()
     print (px[4,4])
     px[4,4] = (0,0,0)