code: def test_has_node_functionality(dask_client, input_combo):
      G = input_combo["MGGraph"]
  
      valid_nodes = G.nodes().compute()
  
      # randomly sample k nodes from the graph
      k = random.randint(1, 20)
      n = valid_nodes.sample(k).reset_index(drop=True)
      print("nodes are \n", n)
  
      assert G.has_node(n)
  
      invalid_node = valid_nodes.max() + 1
  
      assert G.has_node(invalid_node) is False
  
imports: import gc
  import random
  import pytest
  import copy
  import cupy
  import cudf
  import cugraph
  import dask_cudf
  import cugraph.dask
  import cugraph.dask.comms.comms
  from cugraph.testing import utils
  from dask.distributed import wait
  from pylibcugraph import ResourceHandle
  from pylibcugraph import bfs
  from cudf.testing.testing import assert_frame_equal
  from cugraph.dask.traversal.bfs import convert_to_cudf
  from cugraph.dask.common.input_utils import get_distributed_data
  from pylibcugraph.testing.utils import gen_fixture_params_product
  from cugraph.dask.common.part_utils import persist_dask_df_equal_parts_per_worker
label_desc: Use image node_id 4 for calling a global function with example usage: test_has_node_functionality(dask_client, input_combo) without return types