def on_fit_start(self, trainer: Trainer, pl_module: LightningModule) -> None:
        """Called when fit begins.

        Records the start time of the training process.

        Args:
            trainer (Trainer): PyTorch Lightning trainer instance
            pl_module (LightningModule): The current training module

        Note:
            The trainer and module arguments are not used but kept for callback signature compatibility
        """
        del trainer, pl_module  # These variables are not used.
        self.start = time.time()
Called when fit begins.

        Records the start time of the training process.

        Args:
            trainer (Trainer): PyTorch Lightning trainer instance
            pl_module (LightningModule): The current training module

        Note:
            The trainer and module arguments are not used but kept for callback signature compatibility
        
src/anomalib/callbacks/timer.py