diff -r 27adb952813b Doc/library/random.rst
--- a/Doc/library/random.rst	Sun Nov 13 04:11:37 2011 +0100
+++ b/Doc/library/random.rst	Sun Nov 13 17:40:00 2011 +0100
@@ -90,6 +90,14 @@
    as an optional part of the API. When available, :meth:`getrandbits` enables
    :meth:`randrange` to handle arbitrarily large ranges.
 
+.. function:: getrandbytes(n)
+
+   Returns a :class:`bytes` object with *n* random bytes. This method is
+   supplied with the MersenneTwister generator and some other generators may
+   also provide it as an optional part of the API.
+
+   .. versionadded:: 3.3
+
 
 Functions for integers:
 
diff -r 27adb952813b Lib/test/test_random.py
--- a/Lib/test/test_random.py	Sun Nov 13 04:11:37 2011 +0100
+++ b/Lib/test/test_random.py	Sun Nov 13 17:40:00 2011 +0100
@@ -213,6 +213,26 @@
         self.assertRaises(ValueError, self.gen.getrandbits, -1)
         self.assertRaises(TypeError, self.gen.getrandbits, 10.1)
 
+    def test_genrandbytes(self):
+        # Verify ranges
+        for n in range(1000):
+            self.assertEquals(len(self.gen.getrandbytes(n)), n)
+
+        # Verify all bytes active
+        getbytes = self.gen.getrandbytes
+        for span in [1, 2, 3, 4, 31, 32, 33, 34]:
+            cum = set()
+            for i in range(100):
+                val = getbytes(span)
+                cum |= set(i for i in range(span) if val[i])
+            self.assertEqual(len(cum), span)
+
+        # Verify argument checking
+        self.assertRaises(TypeError, self.gen.getrandbytes)
+        self.assertRaises(TypeError, self.gen.getrandbytes, 1, 2)
+        self.assertRaises(ValueError, self.gen.getrandbytes, -1)
+        self.assertRaises(TypeError, self.gen.getrandbytes, 10.1)
+
     def test_randbelow_logic(self, _log=log, int=int):
         # check bitcount transition points:  2**i and 2**(i+1)-1
         # show that: k = int(1.001 + _log(n, 2))
diff -r 27adb952813b Modules/_randommodule.c
--- a/Modules/_randommodule.c	Sun Nov 13 04:11:37 2011 +0100
+++ b/Modules/_randommodule.c	Sun Nov 13 17:40:00 2011 +0100
@@ -411,6 +411,42 @@
 }
 
 static PyObject *
+random_getrandbytes(RandomObject *self, PyObject *args)
+{
+    Py_ssize_t i, bytes;
+    char *bytearray;
+    PyObject *result;
+
+    if (!PyArg_ParseTuple(args, "n:getrandbytes", &bytes))
+        return NULL;
+
+    if (bytes < 0) {
+        PyErr_SetString(PyExc_ValueError,
+                        "number of bytes must be greater than zero");
+        return NULL;
+    }
+
+    result = PyBytes_FromStringAndSize(NULL, bytes);
+    if (result == NULL)
+        return NULL;
+    bytearray = PyBytes_AS_STRING(result);
+
+    i = 0;
+    while (i < bytes) {
+        unsigned long r = genrand_int32(self);
+        bytearray[i++] = (char)r;
+        if (i < bytes)
+            bytearray[i++] = (char)(r >> 8);
+        if (i < bytes)
+            bytearray[i++] = (char)(r >> 16);
+        if (i < bytes)
+            bytearray[i++] = (char)(r >> 24);
+    }
+
+    return result;
+}
+
+static PyObject *
 random_new(PyTypeObject *type, PyObject *args, PyObject *kwds)
 {
     RandomObject *self;
@@ -443,6 +479,9 @@
     {"getrandbits",     (PyCFunction)random_getrandbits,  METH_VARARGS,
         PyDoc_STR("getrandbits(k) -> x.  Generates a long int with "
                   "k random bits.")},
+    {"getrandbytes",     (PyCFunction)random_getrandbytes,  METH_VARARGS,
+        PyDoc_STR("getrandbytes(n) -> x.  Generates a bytes string with "
+                  "n random bytes.")},
     {NULL,              NULL}           /* sentinel */
 };