def main_output(
        self, func: Callable, sig: Signature, bindings: BoundArguments, ret: Any
    ) -> serial_utils.JSON:
        """
        Determine the main out string for the given function `func` with
        signature `sig` after it is called with the given `bindings` and has
        returned `ret`.
        """

        if isinstance(ret, dict):
            if "content" in ret:
                return ret["content"]

        return json_utils.jsonify(ret)

        Determine the main out string for the given function `func` with
        signature `sig` after it is called with the given `bindings` and has
        returned `ret`.
        
src/apps/nemo/trulens/apps/nemo/tru_rails.py