code: def omega(cls, p_star, alpha):
      return (1 - (p_star**alpha).sum(dim=1)) / (alpha * (alpha - 1))
  
imports: import torch
  import torch.nn
  from torch.autograd import Function
  from ludwig.constants import IGNORE_INDEX_TOKEN_ID
  from ludwig.utils.entmax.activations import entmax15, sparsemax
  from ludwig.utils.entmax.root_finding import entmax_bisect, sparsemax_bisect
label_desc: Use image node_id 2 for calling the EntmaxBisectLossFunction obj's underlying member method code with example usage: obj.omega(cls, p_star, alpha) and returns: unknown