class structural_attention_layer(nn.Module):
def init(self):
super(structural_attention_layer,self).init()
    def forward(self,hello,world):
        return torch.randn(node_num,emb_size)



s_att=nn.Sequential()
s_att.add_module(name=“structural_attention_layer”,module=structural_attention_layer())
s_att(1,2)

error occurs like the title,why?