text: import torch
  import torch_geometric.transforms as T
  from torch_geometric.data import Data
  
  
  def test_compose():
      transform = T.Compose([T.Center(), T.AddSelfLoops()])
      assert transform.__repr__() == ('Compose([\n'
                                      '    Center(),\n'
                                      '    AddSelfLoops(),\n'
                                      '])')
  
      pos = torch.Tensor([[0, 0], [2, 0], [4, 0]])
      edge_index = torch.tensor([[0, 1, 1, 2], [1, 0, 2, 1]])
  
      data = Data(edge_index=edge_index, pos=pos)
      data = transform(data)
      assert len(data) == 2
      assert data.pos.tolist() == [[-2, 0], [0, 0], [2, 0]]
      assert data.edge_index.size() == (2, 7)
  