InvalidUpdateError

[itzmechandruganeshan]

This is my code:

from agents.graph import _print_event
from agents.graph import compiled_graph

configure = {
    "configurable": {
        "thread_id": 1
    }
}

_printed = set()
while True:
    question = input("User: ")
    
    # Get the event generator
    sessions = compiled_graph.stream({"messages": ("user", question)},configure, stream_mode="values")

    # Iterate over events from the generator
    for session in sessions:
        print(session)
        _print_event(session, _printed)

I am getting this error:

Traceback (most recent call last):
  File "D:\ISPG\structured-chatbot\context_aware_bot\main.py", line 18, in <module>
    for session in sessions:
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langgraph\pregel\__init__.py", line 1303, in stream
    _panic_or_proceed(all_futures, loop.step)
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langgraph\pregel\__init__.py", line 1733, in _panic_or_proceed
    raise exc
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langgraph\pregel\executor.py", line 59, in done
    task.result()
  File "D:\ISPG\langgrach-chatbot\venv\Lib\concurrent\futures\_base.py", line 449, in result
    return self.__get_result()
           ^^^^^^^^^^^^^^^^^^^
  File "D:\ISPG\langgrach-chatbot\venv\Lib\concurrent\futures\_base.py", line 401, in __get_result
    raise self._exception
  File "D:\ISPG\langgrach-chatbot\venv\Lib\concurrent\futures\thread.py", line 58, in run
    result = self.fn(*self.args, **self.kwargs)
             ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langgraph\pregel\retry.py", line 26, in run_with_retry
    task.proc.invoke(task.input, task.config)
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langgraph\utils.py", line 93, in invoke
    ret = self._call_with_config(
          ^^^^^^^^^^^^^^^^^^^^^^^
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langchain_core\runnables\base.py", line 1785, in _call_with_config
    context.run(
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langchain_core\runnables\config.py", line 398, in call_func_with_variable_args
    return func(input, **kwargs)  # type: ignore[call-arg]
           ^^^^^^^^^^^^^^^^^^^^^
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langgraph\pregel\write.py", line 107, in _write
    self.do_write(
  File "D:\ISPG\langgrach-chatbot\venv\Lib\site-packages\langgraph\pregel\write.py", line 157, in do_write
    raise InvalidUpdateError(
langgraph.errors.InvalidUpdateError: Must write to at least one of []

Can anyone help me with this issue?