code: def test_to_fixed_size():
      x = torch.randn(10, 16)
      batch = torch.zeros(10, dtype=torch.long)
  
      model = Model()
      assert model(x, batch).size() == (1, 16)
  
      model = to_fixed_size(model, batch_size=10)
      assert model(x, batch).size() == (10, 16)
  
imports: import torch
  from torch_geometric.nn import SumAggregation
  from torch_geometric.nn.to_fixed_size_transformer import to_fixed_size
label_desc: Use image node_id 1 for calling a global function with example usage: test_to_fixed_size() without return types