code: def A2():
      diffeq = lambda t, y: -(y**3) / 2
      init = lambda: (torch.tensor(0.0), torch.tensor(1.0))
      solution = lambda t: 1 / torch.sqrt(t + 1)
      return diffeq, init, solution
  
imports: import math
  import torch
label_desc: Use image node_id 2 for calling a global function with example usage: A2() and returns: diffeq,  init,  solution