code: def _zero_loss(x, y):
      return torch.sum(x) * 0.0
  
imports: import copy
  from collections import OrderedDict
  import numpy
  import pytest
  import torch
  from coremltools.optimize.torch.pruning import MagnitudePruner, MagnitudePrunerConfig, ModuleMagnitudePrunerConfig
  from coremltools.optimize.torch.pruning._utils import n_m_mask
label_desc: Use image node_id 1 for calling a global function with example usage: _zero_loss(x, y) and returns: unknown