code: def forward(self, x, cross, x_mask=None, cross_mask=None):
      for layer in self.layers:
          x = layer(x, cross, x_mask=x_mask, cross_mask=cross_mask)
  
      if self.norm is not None:
          x = self.norm(x)
  
      if self.projection is not None:
          x = self.projection(x)
      return x
  
file_path: merlion/merlion/models/utils/nn_modules/enc_dec_transformer.py
imports: import math
label_desc: Use image node_id 2 for calling the Decoder obj's underlying member method code with example usage: obj.forward(x, cross, x_mask, cross_mask) and returns: x