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# SPDX-License-Identifier: Apache-2.0
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
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#
# http://www.apache.org/licenses/LICENSE-2.0
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# Unless required by applicable law or agreed to in writing, software
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from typing import Optional

import torch
import torch.distributed

from cosmos_predict2._src.imaginaire.checkpointer.base import AbstractCheckpointer
from cosmos_predict2._src.imaginaire.model import ImaginaireModel


class Checkpointer(AbstractCheckpointer):
    """
    A dummy checkpointer that does not save or load anything. This is useful for debugging jobs or share workload with collobrators.
    """

    def save(
        self,
        model: ImaginaireModel,
        optimizer: torch.optim.Optimizer,
        scheduler: torch.optim.lr_scheduler.LRScheduler,
        grad_scaler: torch.amp.GradScaler,
        iteration: int,
    ) -> None:
        pass

    def load(
        self,
        model: ImaginaireModel,
        optimizer: Optional[torch.optim.Optimizer] = None,
        scheduler: Optional[torch.optim.lr_scheduler.LRScheduler] = None,
        grad_scaler: Optional[torch.amp.GradScaler] = None,
    ) -> int:
        return 0