code: def convert_to_pairs(indices_tuple, labels, ref_labels=None):
      """
      This returns anchor-positive and anchor-negative indices,
      regardless of what the input indices_tuple is
      Args:
          indices_tuple: tuple of tensors. Each tensor is 1d and specifies indices
                          within a batch
          labels: a tensor which has the label for each element in a batch
      """
      if indices_tuple is None:
          return get_all_pairs_indices(labels, ref_labels)
      elif len(indices_tuple) == 4:
          return indices_tuple
      else:
          a, p, n = indices_tuple
          return a, p, a, n
  
imports: import math
  import numpy
  import torch
  from .None import common_functions
label_desc: Use image node_id 5 for calling a global function with example usage: convert_to_pairs(indices_tuple, labels, ref_labels) and returns: get_all_pairs_indices, indices_tuple, a,  p,  a,  n