code: def mine(self, embeddings, labels, ref_emb, ref_labels):
      batch_size = embeddings.size(0)
      a = torch.arange(0, batch_size, 3)
      p = torch.arange(1, batch_size, 3)
      n = torch.arange(2, batch_size, 3)
      return a, p, n
  
imports: import torch
  from .base_miner import BaseMiner
label_desc: Use image node_id 1 for calling the EmbeddingsAlreadyPackagedAsTriplets obj's underlying member method code with example usage: obj.mine(embeddings, labels, ref_emb, ref_labels) and returns: a,  p,  n