Do not use explicit inheritance from object in the documentation. (GH-13936)

diff --git a/Doc/library/copyreg.rst b/Doc/library/copyreg.rst
index 40fca56..4392021 100644
--- a/Doc/library/copyreg.rst
+++ b/Doc/library/copyreg.rst
@@ -49,7 +49,7 @@
 it will be used:
 
    >>> import copyreg, copy, pickle
-   >>> class C(object):
+   >>> class C:
    ...     def __init__(self, a):
    ...         self.a = a
    ...