Issue #17765: weakref.ref() no longer silently ignores keyword arguments.

Patch by Georg Brandl.

diff --cc Misc/NEWS
Simple merge

diff --cc Objects/weakrefobject.c
index f42fe3d59dd0b9795be1057b2c302cc41b25a51f,7e6f36458bc693cffeee1e329196e0af0da9e52d..f75b1e83a8cec650e06a848349aa6f0e1461b0a6
--- 1/Objects/weakrefobject.c
--- 2/Objects/weakrefobject.c
+++ b/Objects/weakrefobject.c
@@@ -265,10 -265,9 +265,9 @@@ insert_head(PyWeakReference *newref, Py
  }
  
  static int
 -parse_weakref_init_args(char *funcname, PyObject *args, PyObject *kwargs,
 +parse_weakref_init_args(const char *funcname, PyObject *args, PyObject *kwargs,
                          PyObject **obp, PyObject **callbackp)
  {
-     /* XXX Should check that kwargs == NULL or is empty. */
      return PyArg_UnpackTuple(args, funcname, 1, 2, obp, callbackp);
  }