class_docstr: Two-layer feed-forward module.
  
  Args:
      d_in (int): The dimension of the input for feedforward
          network model.
      d_hid (int): The dimension of the feedforward
          network model.
      dropout (float): Dropout layer on feedforward output.
      act_cfg (dict): Activation cfg for feedforward module.
code: def forward(self, x):
      x = self.w_1(x)
      x = self.act(x)
      x = self.w_2(x)
      x = self.dropout(x)
  
      return x
  
imports: import numpy
  import torch
  import torch.nn
  import torch.nn.functional
  from mmocr.registry import MODELS
label_desc: Use image node_id 2 for calling the PositionwiseFeedForward obj's underlying member method code with example usage: obj.forward(x) and returns: x