code: def posterior_to_xarray(self):
          
          data = {}
          for i, var_name in enumerate(self.var_names):
              data[var_name] = np.expand_dims(self.posterior[i], axis=0)
          return dict_to_dataset(data, library=self.tfp, coords=self.coords, dims=self.dims)
docs: Convert the posterior to an xarray dataset.