diff -r 9347869d1066 Modules/_randommodule.c
--- a/Modules/_randommodule.c	Thu Dec 13 19:09:33 2012 +0200
+++ b/Modules/_randommodule.c	Thu Dec 13 22:46:40 2012 +0200
@@ -389,6 +389,9 @@
         return NULL;
     }
 
+    if (k <= 32)  /* Fast path */
+        return PyLong_FromUnsignedLong(genrand_int32(self) >> (32 - k));
+
     bytes = ((k - 1) / 32 + 1) * 4;
     bytearray = (unsigned char *)PyMem_Malloc(bytes);
     if (bytearray == NULL) {