examples/research_projects/bertabs/modeling_bertabs.py/PositionwiseFeedForward/forward
class PositionwiseFeedForward:    def forward(self, x):
        inter = self.dropout_1(self.actv(self.w_1(self.layer_norm(x))))
        output = self.dropout_2(self.w_2(inter))
        return output + x