code: def density_3D(tensor):
      """Filter-wise density for 4D tensors"""
      return 1 - sparsity_3D(tensor)
  
imports: import argparse
  from collections import OrderedDict
  from copy import deepcopy
  import logging
  import operator
  import random
  import numpy
  import torch
  import torch.nn
  import torch.backends.cudnn
  import yaml
  import inspect
label_desc: Use image node_id 15 for calling a global function with example usage: density_3D(tensor) and returns: unknown