def before_eval(
        self,
        strategy: "SupervisedTemplate",
        metric_values: List["MetricValue"],
        **kwargs,
    ):
        """
        Manage the case in which `eval` is first called before `train`
        """
        if self.in_train_phase is None:
            self.in_train_phase = False

        Manage the case in which `eval` is first called before `train`
        
avalanche/logging/csv_logger.py