code: def calculate_logits(self, joint_embedding, **kwargs):
      return self.classifier(joint_embedding)
  
imports: import copy
  import omegaconf
  import torch
  from mmf.common.registry import registry
  from mmf.models.base_model import BaseModel
  from mmf.modules.embeddings import ImageFeatureEmbedding, MultiHeadImageFeatureEmbedding, PreExtractedEmbedding, TextEmbedding
  from mmf.modules.layers import ClassifierLayer, ModalCombineLayer
  from mmf.utils.build import build_image_encoder
  from torch import nn
label_desc: Use image node_id 19 for calling the Pythia obj's underlying member method code with example usage: obj.calculate_logits(joint_embedding) and returns: self