code: def betas_from_alpha_bar(alpha_bar):
      alphas = torch.cat(
          [torch.Tensor([alpha_bar[0]]), alpha_bar[1:] / alpha_bar[:-1]]
      )
      return 1 - alphas
  
imports: from collections import namedtuple
  import random
  import typing
  import julius
  import torch
label_desc: Use image node_id 1 for calling a global function with example usage: betas_from_alpha_bar(alpha_bar) and returns: unknown