def setup_optimizers(self, *optimizers: Optimizer) -> Union[_FabricOptimizer, tuple[_FabricOptimizer, ...]]:
        r"""Set up one or more optimizers for accelerated training.

        Some strategies do not allow setting up model and optimizer independently. For them, you should call
        ``.setup(model, optimizer, ...)`` instead to jointly set them up.

        Args:
            *optimizers: One or more optmizers to set up.

        Returns:
            The wrapped optimizer(s).

        """
        self._validate_setup_optimizers(optimizers)
        optimizers = [self._strategy.setup_optimizer(optimizer) for optimizer in optimizers]
        optimizers = [
            _FabricOptimizer(optimizer=optimizer, strategy=self._strategy, callbacks=self._callbacks)
            for optimizer in optimizers
        ]
        return optimizers[0] if len(optimizers) == 1 else tuple(optimizers)
Set up one or more optimizers for accelerated training.

        Some strategies do not allow setting up model and optimizer independently. For them, you should call
        ``.setup(model, optimizer, ...)`` instead to jointly set them up.

        Args:
            *optimizers: One or more optmizers to set up.

        Returns:
            The wrapped optimizer(s).

        
src/lightning/fabric/fabric.py