class_docstr: Test for the MultiInterface and GeomDictInterface.
code: def test_multi_dict_groupby(self):
      geoms = [
          {"geometry": sgeom.Polygon([(2, 0), (1, 2), (0, 0)]), "z": 1},
          {"geometry": sgeom.Polygon([(3, 3), (3, 3), (6, 0)]), "z": 2},
      ]
      mds = Dataset(
          geoms, kdims=["x", "y", "z"], datatype=[self.datatype]
      )
      for i, (k, ds) in enumerate(mds.groupby("z").items()):
          self.assertEqual(k, geoms[i]["z"])
          self.assertEqual(
              ds.clone(vdims=[]), Dataset([geoms[i]], kdims=["x", "y"])
          )
  
imports: from unittest import SkipTest
  import numpy
  import pandas
  from holoviews.core.data import Dataset, MultiInterface
  from holoviews.core.data.interface import DataError
  from holoviews.element import Polygons, Path
  from holoviews.element.comparison import ComparisonTestCase
  from holoviews.tests.core.data.test_multiinterface import MultiBaseInterfaceTest
  from geoviews.data.geom_dict import GeomDictInterface
label_desc: Use image node_id 15 for calling the GeomInterfaceTest obj's underlying member method code with example usage: obj.test_multi_dict_groupby() without return types