code: def forward(self, g, l_g):
      g.apply_edges(self.edge_transfer)
  
      # nodes correspond to edges and edges correspond to nodes in the original graphs
      # node: d, rbf, o, rbf_env, x_kj, x_ji
      for k, v in g.edata.items():
          l_g.ndata[k] = v
  
      l_g_reverse = dgl.reverse(l_g, copy_edata=True)
      l_g_reverse.update_all(self.msg_func, fn.sum("x_kj", "m_update"))
  
      g.edata["m_update"] = self.up_projection(
          l_g_reverse.ndata["m_update"]
      )
      if self.activation is not None:
          g.edata["m_update"] = self.activation(g.edata["m_update"])
      # Transformations before skip connection
      g.edata["m_update"] = g.edata["m_update"] + g.edata["x_ji"]
      for layer in self.layers_before_skip:
          g.edata["m_update"] = layer(g.edata["m_update"])
      g.edata["m_update"] = self.final_before_skip(g.edata["m_update"])
      if self.activation is not None:
          g.edata["m_update"] = self.activation(g.edata["m_update"])
  
      # Skip connection
      g.edata["m"] = g.edata["m"] + g.edata["m_update"]
  
      # Transformations after skip connection
      for layer in self.layers_after_skip:
          g.edata["m"] = layer(g.edata["m"])
  
      return g
  
file_path: dgl/examples/pytorch/dimenet/modules/interaction_pp_block.py
imports: import dgl
  import dgl.function
  import torch.nn
  from modules.initializers import GlorotOrthogonal
  from modules.residual_layer import ResidualLayer
label_desc: Use image node_id 5 for calling the InteractionPPBlock obj's underlying member method code with example usage: obj.forward(g, l_g) and returns: g