bpo-42620: Improve socket.getsockname doc string (GH-23742)

Signed-off-by: Christian Heimes <[email protected]>
(cherry picked from commit cf3565c)

Co-authored-by: Christian Heimes <[email protected]>

Author: miss-islington

Modules/socketmodule.c

@@ -3407,8 +3407,9 @@ sock_getsockname(PySocketSockObject *s, PyObject *Py_UNUSED(ignored))
 PyDoc_STRVAR(getsockname_doc,
 "getsockname() -> address info\n\
 \n\
-Return the address of the local endpoint.  For IP sockets, the address\n\
-info is a pair (hostaddr, port).");
+Return the address of the local endpoint. The format depends on the\n\
+address family. For IPv4 sockets, the address info is a pair\n\
+(hostaddr, port).");
 
 
 #ifdef HAVE_GETPEERNAME         /* Cray APP doesn't have this :-( */