Added type hints to example code

docs/handbook/image-file-formats.rst

@@ -1517,19 +1517,21 @@ To add other read or write support, use
 :py:func:`PIL.WmfImagePlugin.register_handler` to register a WMF and EMF
 handler. ::
 
-    from PIL import Image
+    from typing import IO
+
+    from PIL import Image, ImageFile
     from PIL import WmfImagePlugin
 
 
-    class WmfHandler:
+    class WmfHandler(ImageFile.StubHandler):
-        def open(self, im):
+        def open(self, im: ImageFile.StubImageFile) -> None:
             ...
 
-        def load(self, im):
+        def load(self, im: ImageFile.StubImageFile) -> Image.Image:
             ...
             return image
 
-        def save(self, im, fp, filename):
+        def save(self, im: Image.Image, fp: IO[bytes], filename: str) -> None:
             ...
 
 

docs/handbook/tutorial.rst

@@ -186,7 +186,7 @@ Rolling an image
 
 ::
 
-    def roll(im, delta):
+    def roll(im: Image.Image, delta: int) -> Image.Image:
         """Roll an image sideways."""
         xsize, ysize = im.size
 
@@ -211,7 +211,7 @@ Merging images
 
 ::
 
-    def merge(im1, im2):
+    def merge(im1: Image.Image, im2: Image.Image) -> Image.Image:
         w = im1.size[0] + im2.size[0]
         h = max(im1.size[1], im2.size[1])
         im = Image.new("RGBA", (w, h))
@@ -704,7 +704,7 @@ in the current directory can be saved as JPEGs at reduced quality.
     import glob
     from PIL import Image
 
-    def compress_image(source_path, dest_path):
+    def compress_image(source_path: str, dest_path: str) -> None:
         with Image.open(source_path) as img:
             if img.mode != "RGB":
                 img = img.convert("RGB")

docs/handbook/writing-your-own-image-plugin.rst

@@ -53,7 +53,7 @@ true color.
     from PIL import Image, ImageFile
 
 
-    def _accept(prefix):
+    def _accept(prefix: bytes) -> bool:
         return prefix[:4] == b"SPAM"
 
 
@@ -62,7 +62,7 @@ true color.
         format = "SPAM"
         format_description = "Spam raster image"
 
-        def _open(self):
+        def _open(self) -> None:
 
             header = self.fp.read(128).split()
 
@@ -82,7 +82,7 @@ true color.
                 raise SyntaxError(msg)
 
             # data descriptor
-            self.tile = [("raw", (0, 0) + self.size, 128, (self.mode, 0, 1))]
+            self.tile = [ImageFile._Tile("raw", (0, 0) + self.size, 128, (self.mode, 0, 1))]
 
 
     Image.register_open(SpamImageFile.format, SpamImageFile, _accept)