Quick fixes for assert failures in dbm wrapper code.

Modules/dbmmodule.c

@@ -103,8 +103,7 @@ dbm_subscript(dbmobject *dp, register PyObject *key)
         check_dbmobject_open(dp);
 	drec = dbm_fetch(dp->di_dbm, krec);
 	if ( drec.dptr == 0 ) {
-		PyErr_SetString(PyExc_KeyError,
-				PyString_AS_STRING((PyStringObject *)key));
+		PyErr_SetObject(PyExc_KeyError, key);
 		return NULL;
 	}
 	if ( dbm_error(dp->di_dbm) ) {
@@ -135,8 +134,7 @@ dbm_ass_sub(dbmobject *dp, PyObject *v, PyObject *w)
 	if (w == NULL) {
 		if ( dbm_delete(dp->di_dbm, krec) < 0 ) {
 			dbm_clearerr(dp->di_dbm);
-			PyErr_SetString(PyExc_KeyError,
-				      PyString_AS_STRING((PyStringObject *)v));
+			PyErr_SetString(PyExc_KeyError, v);
 			return -1;
 		}
 	} else {