code: def test_groupby_nested_dict(func):
      pdf = pd.DataFrame(
          {
              "x": np.random.randint(0, 5, size=10000),
              "y": np.random.normal(size=10000),
          }
      )
  
      ddf = dd.from_pandas(pdf, npartitions=5)
      c_ddf = ddf.map_partitions(cudf.from_pandas)
  
      a = func(ddf).compute()
      b = func(c_ddf).compute().to_pandas()
  
      a.index.name = None
      a.name = None
      b.index.name = None
      b.name = None
  
      dd.assert_eq(a, b)
  
imports: import numpy
  import pandas
  import pytest
  import dask
  from dask import dataframe
  from dask.utils_test import hlg_layer
  import cudf
  import dask_cudf
  from dask_cudf.groupby import OPTIMIZED_AGGS, _aggs_optimized
label_desc: Use image node_id 28 for calling a global function with example usage: test_groupby_nested_dict(func) without return types