Merge pull request #3846 from radarhere/doc

Documentation fixes

docs/handbook/tutorial.rst

@@ -473,8 +473,8 @@ Reading from a string
 
 ::
 
+    from PIL import Image
     import StringIO
-
     im = Image.open(StringIO.StringIO(buffer))
 
 Note that the library rewinds the file (using ``seek(0)``) before reading the

docs/handbook/writing-your-own-file-decoder.rst

@@ -255,9 +255,10 @@ If the raw decoder cannot handle your format, PIL also provides a special “bit
 decoder that can be used to read various packed formats into a floating point
 image memory.
 
-To use the bit decoder with the frombytes function, use the following syntax::
+To use the bit decoder with the :py:func:`PIL.Image.frombytes` function, use
+the following syntax::
 
-    image = frombytes(
+    image = Image.frombytes(
         mode, size, data, "bit",
         bits, pad, fill, sign, orientation
         )

docs/reference/ImageMath.rst

@@ -5,8 +5,8 @@
 ==========================
 
 The :py:mod:`ImageMath` module can be used to evaluate “image expressions”. The
-module provides a single eval function, which takes an expression string and
-one or more images.
+module provides a single :py:meth:`~PIL.ImageMath.eval` function, which takes
+an expression string and one or more images.
 
 Example: Using the :py:mod:`~PIL.ImageMath` module
 --------------------------------------------------