from typing import Union
import torch

def set_device(device : Union[str, torch.device]) -> torch.device:
    """
    Set the device to use for inference. Recommended to use GPU.
    Arguments:
        device Union[str, torch.device]
            The device to use for inference. Can be either a string or a torch.device object.

    Returns:
        torch.device
            The device to use for inference.
    """
    if isinstance(device, str):
        if device == 'cuda' and torch.cuda.is_available():
            device = torch.device('cuda' if torch.cuda.is_available() else 'cpu')
        elif device == 'mps' and torch.backends.mps.is_built():
            device = torch.device('mps') 
        else:
            device = torch.device(device)
    return device