code: def setup_function():
      global DiGraph_inst
  
      gc.collect()
      # Set the global DiGraph_inst. This is used for calls that require a Graph
      # type or instance to be provided for tests that use a directed graph.
      DiGraph_inst = cugraph.Graph(directed=True)
  
imports: import gc
  import pytest
  import pandas
  import numpy
  import cudf
  import cugraph
  import dask_cudf
  import cupy
  import cugraph.dask
  from cupy.testing import assert_array_equal
  from cudf.testing import assert_frame_equal, assert_series_equal
  from pylibcugraph.testing.utils import gen_fixture_params_product
  from cugraph.dask.common.mg_utils import is_single_gpu
  from cugraph.datasets import cyber, netscience
label_desc: Use image node_id 2 for calling a global function with example usage: setup_function() without return types