def test_gcn_conv_norm():
x = torch.randn(4, 16)
edge_index = torch.tensor([[0, 0, 0], [1, 2, 3]])
row, col = edge_index
conv = GCNConv(16, 32, flow="source_to_target")
out1 = conv(x, edge_index)
conv.flow = "target_to_source"
out2 = conv(x, edge_index.flip(0))
assert torch.allclose(out1, out2, atol=1e-6)
