chore: update news and add comment

Author: yanyongyu

Lib/inspect.py

@@ -1917,10 +1917,14 @@ def _signature_get_user_defined_method(cls, method_name, *, follow_wrapper_chain
     if meth is None:
         return None
 
+    # NOTE: The meth may wraps a non-user-defined callable.
+    # In this case, we treat the meth as non-user-defined callable too.
+    # (e.g. cls.__new__ generated by @warnings.deprecated)
     unwrapped_meth = None
     if follow_wrapper_chains:
         unwrapped_meth = unwrap(meth, stop=(lambda m: hasattr(m, "__signature__")
                                   or _signature_is_builtin(m)))
+
     if (isinstance(meth, _NonUserDefinedCallables)
           or isinstance(unwrapped_meth, _NonUserDefinedCallables)):
         # Once '__signature__' will be added to 'C'-level

Misc/NEWS.d/next/Library/2025-08-16-16-04-15.gh-issue-137317.Dl13B5.rst

@@ -1,2 +1,2 @@
-Fix the behavior when using :func:`inspect.signature` to get the signature
-for a class that uses descriptor on a wrapped :meth:`!__init__` methods.
+:func:`inspect.signature` now correctly handles classes that use a descriptor
+on a wrapped :meth:`!__init__` or :meth:`!__new__` method.