code: def laplace3d():
      l = np.zeros((3, 3, 3))
      l[1, 1, 1] = -6.0
      l[1, 1, 2] = 1.0
      l[1, 1, 0] = 1.0
      l[1, 0, 1] = 1.0
      l[1, 2, 1] = 1.0
      l[0, 1, 1] = 1.0
      l[2, 1, 1] = 1.0
      return l.astype(np.float32)[None, None, ...]
  
imports: import torch.nn
  import numpy
  import torch
label_desc: Use image node_id 2 for calling a global function with example usage: laplace3d() and returns: l