Add weakref support to sockets and re pattern objects.

Doc/whatsnew/whatsnew24.tex

@@ -558,6 +558,10 @@ For example:
    earlier in the expression.  If the specified group matched, the
    regular expression pattern \var{A} will be tested against the string; if
    the group didn't match, the pattern \var{B} will be used instead.
+
+\item The \module{weakref} module now supports a wider variety of objects
+   including Python functions, class instances, sets, frozensets, deques,
+   arrays, files, sockets, and regular expression pattern objects.
    
 \end{itemize}