code: def get_map_location(target_device, fallback_device='cpu'):
      
      map_location = torch.device(target_device)
  
      # The user wants to use CUDA but there is no CUDA device
      # available, thus fall back to CPU.
      if map_location.type == 'cuda' and not torch.cuda.is_available():
          warnings.warn(
              'Requested to load data to CUDA but no CUDA devices '
              'are available. Loading on device "{}" instead.'.format(
                  fallback_device,
              ), DeviceWarning)
          map_location = torch.device(fallback_device)
      return map_location
docs: Determine the location to map loaded data (e.g., weights)
      for a given target device (e.g. 'cuda').