old_contents: # Copyright The PyTorch Lightning team.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  from collections import Callable
  from typing import Any
  
  from torch.optim import Optimizer
  
  import pytorch_lightning as pl
  from pytorch_lightning.accelerators.accelerator import Accelerator
  from pytorch_lightning.utilities.exceptions import MisconfigurationException
  
  
  class IPUAccelerator(Accelerator):
      """Accelerator for IPUs."""
  
      def setup_optimizers(self, trainer: "pl.Trainer") -> None:
          super().setup_optimizers(trainer)
  
          if len(self.optimizers) > 1:
              raise MisconfigurationException("IPUs currently only support one optimizer.")
  
      def optimizer_step(self, optimizer: Optimizer, opt_idx: int, lambda_closure: Callable, **kwargs: Any) -> None:
          # Optimizer step is handled by the IPU accelerator.
          lambda_closure()
  
new_contents: # Copyright The PyTorch Lightning team.
  #
  # Licensed under the Apache License, Version 2.0 (the "License");
  # you may not use this file except in compliance with the License.
  # You may obtain a copy of the License at
  #
  #     http://www.apache.org/licenses/LICENSE-2.0
  #
  # Unless required by applicable law or agreed to in writing, software
  # distributed under the License is distributed on an "AS IS" BASIS,
  # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  # See the License for the specific language governing permissions and
  # limitations under the License.
  from typing import Any, Callable
  
  from torch.optim import Optimizer
  
  import pytorch_lightning as pl
  from pytorch_lightning.accelerators.accelerator import Accelerator
  from pytorch_lightning.utilities.exceptions import MisconfigurationException
  
  
  class IPUAccelerator(Accelerator):
      """Accelerator for IPUs."""
  
      def setup_optimizers(self, trainer: "pl.Trainer") -> None:
          super().setup_optimizers(trainer)
  
          if len(self.optimizers) > 1:
              raise MisconfigurationException("IPUs currently only support one optimizer.")
  
      def optimizer_step(self, optimizer: Optimizer, opt_idx: int, lambda_closure: Callable, **kwargs: Any) -> None:
          # Optimizer step is handled by the IPU accelerator.
          lambda_closure()
  
subject: Fix an import deprecation warning (#8687)