langchain/cli/main.py/PlusCommand/_start_local
class PlusCommand:    def _start_local(self) -> None:
        command = [
            *self.docker_compose_command,
            "-f",
            str(self.docker_compose_file),
        ]
        subprocess.run(
            [
                *command,
                "up",
                "--pull=always",
                "--quiet-pull",
                "--wait",
            ]
        )
        logger.info(
            "langchain plus server is running at http://localhost.  To connect"
            " locally, set the following environment variable"
            " when running your LangChain application."
        )

        logger.info("\tLANGCHAIN_TRACING_V2=true")
        self._open_browser("http://localhost")