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* added new regions: IPCC WG1 Reference Regions v4 from Atlas
* xweights/_io.py is no longer available
* xweights/_domains.py is no longer available
* function `spatial_averager` -> `spatial_averaging`
* function `compute_weighted_means`:
* optionally: set `averager_ds` to calculate a general xesmf.SpatialAverager
* parameter `shp` -> `gdf`
* parameter `input` -> `dataset_dict`
* parameter `dataset_dict` has to be a dictionary
* parameter `outdir` -> `output`
* function `compute_weighted_means_ds`: parameters are now similar to `compute_weighted_means`
* command-line interface is no longer available