code: def l2_norm(v):
      fnorm = torch.norm(v, p=2, dim=1, keepdim=True) + 1e-6
      v = v.div(fnorm.expand_as(v))
      return v
  
file_path: pytorch-metric-learning/tests/losses/test_instance_loss.py
imports: import unittest
  import numpy
  import torch
  import torch.nn.functional
  from torch import Tensor, nn
  from pytorch_metric_learning.losses import InstanceLoss
  from ..None import TEST_DEVICE, TEST_DTYPES
label_desc: Use image node_id 1 for calling a global function with example usage: l2_norm(v) and returns: v