remove dead code, fix err var, revert newline, fix comment

Author: jadonduff

Lib/test/test_threading.py

@@ -2361,7 +2361,6 @@ def work():
                 thread = threading.Thread(target=work, name=name)
                 thread.start()
                 thread.join()
-                # If the name is non-ASCII and the result is empty, skip (platform limitation)
                 if not name.isascii() and not work_name:
                     self.skipTest(f"Platform does not support non-ASCII thread names: got empty name for {name!r}")
                 self.assertEqual(work_name, expected,

Modules/_threadmodule.c

@@ -113,8 +113,6 @@ encode_thread_name(PyObject *name_obj, const char *encoding)
         PyObject *truncated = PyBytes_FromStringAndSize(PyBytes_AS_STRING(name_encoded), _PYTHREAD_NAME_MAXLEN);
         Py_DECREF(name_encoded);
         return truncated;
-        Py_DECREF(name_encoded);
-        return truncated;
     }
 #endif
     return name_encoded;
@@ -2922,4 +2920,4 @@ PyMODINIT_FUNC
 PyInit__thread(void)
 {
     return PyModuleDef_Init(&thread_module);
-}
+}