code: def build(self):
      # modules requiring custom learning rates (usually for finetuning)
      self.finetune_modules = []
  
      # split model building into several components
      self._build_txt_encoding()
      self._build_obj_encoding()
      self._build_ocr_encoding()
      self._build_mmt()
      self._build_output()
  
imports: import functools
  import logging
  import math
  import torch
  import torch.nn.functional
  from mmf.common.registry import registry
  from mmf.models.base_model import BaseModel
  from mmf.modules.layers import ClassifierLayer
  from mmf.utils.build import build_image_encoder
  from omegaconf import OmegaConf
  from torch import nn
label_desc: Use image node_id 3 for calling the M4C obj's underlying member method code with example usage: obj.build() without return types