code: def test_ClusterNodeSequence_cluster_without_targets():
      G = create_stellargraph()
      generator = ClusterNodeGenerator(G, clusters=2, q=1)
      seq = generator.flow(node_ids=["a"], targets=[0])
      _ = list(seq)
  
file_path: stellargraph/tests/mapper/test_cluster_gcn_node_mapper.py
imports: from stellargraph.mapper import ClusterNodeGenerator, ClusterNodeSequence
  from stellargraph.core.graph import StellarGraph
  import pandas
  import numpy
  import pytest
  from ..test_utils.graphs import example_graph_random
label_desc: Use image node_id 8 for calling a global function with example usage: test_ClusterNodeSequence_cluster_without_targets() without return types