Asyncio : trace_to_thread raise exception when func doesn't has __name__ attribute

[JulienStitelet]

Describe your environment

OS: macos
Python version: 3.11.9
SDK version: 1.27.0
API version: 0.48b0

What happened?

On a fastapi app,
During async stream call to a LLM,
Using Langgraph lib, somehow when reaching this def trace_to_thread(self, func: callable): a partial func is send, without name attribute :

So, the statement if func.__name__ in self._to_thread_name_to_trace is raising an exception, and killing the whole process (not the server)

Steps to Reproduce

The point is I don't own the langgraph lib so I don't know (and I could not figure out) how it's done.
But the problem is pretty easy to understand.

Expected Result

As a telemetry tool, I don't want it to break my app.
worst is it doesn't do the metrics BUT error log it.

Actual Result

Exception raised

Additional context

Can be fix easily like :

     func_name = func.__name__ if hasattr(func, "__name__") and func.__name__ in self._to_thread_name_to_trace else None

      span = (
          self._tracer.start_span(
              f"{ASYNCIO_PREFIX} to_thread-" + func_name
          )
          if func_name and func_name in self._to_thread_name_to_trace
          else None
      )
attr = {"type": "to_thread", "name": func_name}

Would you like to implement a fix?

Yes