diff -r d9828c438889 Doc/library/stdtypes.rst
--- a/Doc/library/stdtypes.rst	Sat May 25 18:48:16 2013 +0200
+++ b/Doc/library/stdtypes.rst	Sat May 25 16:59:40 2013 -0400
@@ -502,6 +502,15 @@
     given, an :exc:`OverflowError` is raised. The default value for *signed*
     is ``False``.
 
+    Equivalent to::
+
+        def to_bytes(n, length, byteorder, signed=False):
+            if byteorder == 'little':
+                order = range(length)
+            elif byteorder == 'big':
+                order = reversed(range(length))
+            return bytes((n >> i*8) & 0xff for i in order)
+
     .. versionadded:: 3.2
 
 .. classmethod:: int.from_bytes(bytes, byteorder, \*, signed=False)
@@ -532,6 +541,18 @@
     The *signed* argument indicates whether two's complement is used to
     represent the integer.
 
+    Equivalent to::
+
+        def from_bytes(bytes, byteorder, signed=False):
+            if byteorder == 'little':
+                little_ordered = list(bytes)
+            elif byteorder == 'big':
+                little_ordered = list(reversed(bytes))
+            n = sum(little_ordered[i] << i*8 for i in range(len(little_ordered)))
+            if signed and little_ordered and (little_ordered[-1] & 0x80):
+                n -= 1 << 8*len(little_ordered)
+            return n
+
     .. versionadded:: 3.2
 
 
diff -r d9828c438889 Lib/test/test_long.py
--- a/Lib/test/test_long.py	Sat May 25 18:48:16 2013 +0200
+++ b/Lib/test/test_long.py	Sat May 25 16:59:40 2013 -0400
@@ -998,6 +998,12 @@
 
     def test_to_bytes(self):
         def check(tests, byteorder, signed=False):
+            def equivalent_python(n, length, byteorder, signed=False):
+                if byteorder == 'little':
+                    order = range(length)
+                elif byteorder == 'big':
+                    order = reversed(range(length))
+                return bytes((n >> i*8) & 0xff for i in order)
             for test, expected in tests.items():
                 try:
                     self.assertEqual(
@@ -1007,6 +1013,15 @@
                     raise AssertionError(
                         "failed to convert {0} with byteorder={1} and signed={2}"
                         .format(test, byteorder, signed)) from err
+                try:
+                    self.assertEqual(
+                        equivalent_python(test, len(expected), byteorder, signed=signed),
+                        expected)
+                except Exception as err:
+                    raise AssertionError(
+                        "example from docs is not equivalent for conversion of {0} with byteorder={1} and signed={2}"
+                        .format(test, byteorder, signed)) from err
+
 
         # Convert integers to signed big-endian byte arrays.
         tests1 = {
@@ -1097,6 +1112,15 @@
 
     def test_from_bytes(self):
         def check(tests, byteorder, signed=False):
+            def equivalent_python(bytes, byteorder, signed=False):
+                if byteorder == 'little':
+                    little_ordered = list(bytes)
+                elif byteorder == 'big':
+                    little_ordered = list(reversed(bytes))
+                n = sum(little_ordered[i] << i*8 for i in range(len(little_ordered)))
+                if signed and little_ordered and (little_ordered[-1] & 0x80):
+                    n -= 1 << 8*len(little_ordered)
+                return n
             for test, expected in tests.items():
                 try:
                     self.assertEqual(
@@ -1106,6 +1130,14 @@
                     raise AssertionError(
                         "failed to convert {0} with byteorder={1!r} and signed={2}"
                         .format(test, byteorder, signed)) from err
+                try:
+                    self.assertEqual(
+                        equivalent_python(test, byteorder, signed=signed),
+                        expected)
+                except Exception as err:
+                    raise AssertionError(
+                        "example from docs is not equivalent for conversion of {0} with byteorder={1!r} and signed={2}"
+                        .format(test, byteorder, signed)) from err
 
         # Convert signed big-endian byte arrays to integers.
         tests1 = {