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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def checkpoint(global_model, local_model=None):
 """Checkpoint the model. This means we finished a stage of execution. Every time we call check point, there is a version number which will increase by one. Parameters global_model: anytype that can be pickled globally shared model/state when calling this function, the caller need to gauranttees that global_model is the same in all nodes local_model: anytype that can be pickled Local model, that is specific to current node/rank. This can be None when no local state is needed. Notes ----- local_model requires explicit replication of the model for fault-tolerance. This will bring replication cost in checkpoint function. while global_model do not need explicit replication. It is recommended to use global_model if possible. """

    sglobal = pickle.dumps(global_model)
    if local_model is None:
        _LIB.RabitCheckPoint(sglobal, len(sglobal), None, 0)
        del sglobal
    else:
        slocal = pickle.dumps(local_model)
        _LIB.RabitCheckPoint(sglobal, len(sglobal), slocal, len(slocal))
        del slocal
        del sglobal