class_docstr: Implementation of  Dual-Path Convolutional Image-Text Embeddings with Instance Loss, ACM TOMM 2020
  https://arxiv.org/abs/1711.05535
  using cross-entropy loss for every sample if label is not available, else use given label.
code: def get_default_distance(self):
      return CosineSimilarity()
  
file_path: pytorch-metric-learning/src/pytorch_metric_learning/losses/instance_loss.py
imports: import torch
  import torch.nn.functional
  from ..distances import CosineSimilarity
  from ..reducers import MeanReducer
  from ..utils import common_functions
  from .base_metric_loss_function import BaseMetricLossFunction
label_desc: Use image node_id 4 for calling the InstanceLoss obj's underlying member method code with example usage: obj.get_default_distance() and returns: CosineSimilarity