langchain/client/langchain.py/LangChainPlusClient/list_sessions
class LangChainPlusClient:    def list_sessions(self) -> Iterator[TracerSession]:
        """List sessions from the LangChain+ API."""
        response = self._get("/sessions")
        raise_for_status_with_text(response)
        yield from [TracerSession(**session) for session in response.json()]