def main_call(self, human: str) -> str:
        """If available, a single text to a single text invocation of this app."""

        if self.__class__.main_acall is not App.main_acall:
            # Use the async version if available.
            return asynchro_utils.sync(self.main_acall, human)

        raise NotImplementedError()
If available, a single text to a single text invocation of this app.
src/core/trulens/core/app.py