code: def test_empty_input(empty, ord_label, client):
      # prepare LabelEncoder
      n_workers = len(client.has_what())
      empty = dask_cudf.from_cudf(empty, npartitions=n_workers)
      ord_label = dask_cudf.from_cudf(ord_label, npartitions=n_workers)
      le = LabelEncoder()
      le.fit(empty)
      assert le._fitted is True
  
      # test if correctly raies ValueError
      with pytest.raises(
          ValueError, match="y contains previously unseen label"
      ):
          le.inverse_transform(ord_label).compute()
  
      # check fit_transform()
      le = LabelEncoder()
      transformed = le.fit_transform(empty).compute()
      assert le._fitted is True
      assert len(transformed) == 0
  
file_path: cuml/python/cuml/tests/dask/test_dask_label_encoder.py
imports: from cuml.common.exceptions import NotFittedError
  import pytest
  from cuml.internals.safe_imports import cpu_only_import
  import cuml
  from cuml.dask.preprocessing.LabelEncoder import LabelEncoder
  from cuml.internals.safe_imports import gpu_only_import
label_desc: Use image node_id 8 for calling a global function with example usage: test_empty_input(empty, ord_label, client) without return types