diff -r 5dec1604322c Lib/copy.py
--- a/Lib/copy.py	Wed Feb 26 18:26:49 2014 -0500
+++ b/Lib/copy.py	Thu Feb 27 10:24:06 2014 +0100
@@ -110,6 +110,7 @@
 def _copy_immutable(x):
     return x
 for t in (type(None), int, float, bool, str, tuple,
+          bytes,
           frozenset, type, range,
           types.BuiltinFunctionType, type(Ellipsis),
           types.FunctionType, weakref.ref):
diff -r 5dec1604322c Lib/test/test_copy.py
--- a/Lib/test/test_copy.py	Wed Feb 26 18:26:49 2014 -0500
+++ b/Lib/test/test_copy.py	Thu Feb 27 10:24:06 2014 +0100
@@ -98,6 +98,7 @@
             pass
         tests = [None, 42, 2**100, 3.14, True, False, 1j,
                  "hello", "hello\u1234", f.__code__,
+                 b"world", b"\x01\x02 ... \xfe\xff",
                  NewStyle, range(10), Classic, max, WithMetaclass]
         for x in tests:
             self.assertIs(copy.copy(x), x)