bpo-42559: Not that getrandbits() is non-negative. (GH-23843)

diff --git a/Doc/library/random.rst b/Doc/library/random.rst
index c243ace..fa5c74b 100644
--- a/Doc/library/random.rst
+++ b/Doc/library/random.rst
@@ -142,10 +142,11 @@
 
 .. function:: getrandbits(k)
 
-   Returns a Python integer with *k* random bits. This method is supplied with
-   the MersenneTwister generator and some other generators may also provide it
-   as an optional part of the API. When available, :meth:`getrandbits` enables
-   :meth:`randrange` to handle arbitrarily large ranges.
+   Returns a non-negative Python integer with *k* random bits. This method
+   is supplied with the MersenneTwister generator and some other generators
+   may also provide it as an optional part of the API. When available,
+   :meth:`getrandbits` enables :meth:`randrange` to handle arbitrarily large
+   ranges.
 
    .. versionchanged:: 3.9
       This method now accepts zero for *k*.