code: def test_dynamic_hetero_graph_temporal_signal_batch():
      dataset = DynamicHeteroGraphTemporalSignalBatch(
          [None, None],
          [None, None],
          [None, None],
          [None, None],
          [None, None],
      )
      for snapshot in dataset:
          assert len(snapshot.node_types) == 0
          assert len(snapshot.node_stores) == 0
          assert len(snapshot.edge_types) == 0
          assert len(snapshot.edge_stores) == 0
  
imports: import numpy
  import networkx
  from torch_geometric_temporal.signal import temporal_signal_split
  from torch_geometric_temporal.signal import StaticGraphTemporalSignalBatch
  from torch_geometric_temporal.signal import DynamicGraphTemporalSignalBatch
  from torch_geometric_temporal.signal import DynamicGraphStaticSignalBatch
  from torch_geometric_temporal.signal import StaticHeteroGraphTemporalSignalBatch
  from torch_geometric_temporal.signal import DynamicHeteroGraphTemporalSignalBatch
  from torch_geometric_temporal.signal import DynamicHeteroGraphStaticSignalBatch
label_desc: Use image node_id 8 for calling a global function with example usage: test_dynamic_hetero_graph_temporal_signal_batch() without return types