Very minor: Better documentation comment on DeferredError. (#469)

* Better documentation comment on DeferredError.

* Using Napolean-style docstring formatting for example code.

* Fixup flake8 trailing whitespace.

Author: leopd

src/sagemaker/utils.py

@@ -284,10 +284,18 @@ def download_file(bucket_name, path, target, sagemaker_session):
 
 
 class DeferredError(object):
-    """Stores an exception and raises it at a later time anytime this
+    """Stores an exception and raises it at a later time if this
     object is accessed in any way.  Useful to allow soft-dependencies on imports,
     so that the ImportError can be raised again later if code actually
     relies on the missing library.
+
+    Example::
+
+        try:
+            import obscurelib
+        except ImportError as e:
+            logging.warning("Failed to import obscurelib. Obscure features will not work.")
+            obscurelib = DeferredError(e)
     """
 
     def __init__(self, exception):