def experiment(self) -> _FabricExperimentWriter:
        r"""Actual _ExperimentWriter object. To use _ExperimentWriter features in your
        :class:`~lightning.pytorch.core.LightningModule` do the following.

        Example::

            self.logger.experiment.some_experiment_writer_function()

        """
        if self._experiment is not None:
            return self._experiment

        self._fs.makedirs(self.root_dir, exist_ok=True)
        self._experiment = ExperimentWriter(log_dir=self.log_dir)
        return self._experiment
Actual _ExperimentWriter object. To use _ExperimentWriter features in your
        :class:`~lightning.pytorch.core.LightningModule` do the following.

        Example::

            self.logger.experiment.some_experiment_writer_function()

        
src/lightning/pytorch/loggers/csv_logs.py