code: def forward(self, x, padding_mask=None, alibi_bias=None):
      if self.layer_norm_first:
          x = x + self.drop_path(
              self.attn(self.norm1(x), padding_mask, alibi_bias)
          )
          r = x = self.mlp(self.norm2(x))
          t = x
          x = r + self.drop_path(self.post_mlp_dropout(x))
          if not self.ffn_targets:
              t = x
      else:
          x = x + self.drop_path(self.attn(x, padding_mask, alibi_bias))
          r = x = self.norm1(x)
          x = self.mlp(x)
          t = x
          x = self.norm2(r + self.drop_path(self.post_mlp_dropout(x)))
          if not self.ffn_targets:
              t = x
  
      return x, t
  
imports: import torch
  import torch.nn
  import torch.nn.functional
  import numpy
  from dataclasses import dataclass
  from fairseq.modules import LayerNorm, SamePad, SamePad2d, TransposeLast
label_desc: Use image node_id 2 for calling the AltBlock obj's underlying member method code with example usage: obj.forward(x, padding_mask, alibi_bias) and returns: x,  t