 Union = None timesteps: Optional = None  )   Parameters   num_inference_steps (int) —
The number of diffusion steps used when generating samples with a pre-trained model. If used,
timesteps must be None.   device (str or torch.device, optional) —
The device to which the timesteps should be moved to. If None, the timesteps are not moved.   timesteps (List[int], optional) —
Custom timesteps used to support arbitrary spacing between timesteps. If