code: def transform_dict(list_to_transform):
      new_dict = dict()
      for t in list_to_transform:
          user, item, feedback = t[0], t[1], t[2]
          new_dict.setdefault(user, {}).update({item: feedback})
      return new_dict
  
imports: from multiprocessing.pool import Pool
  from random import shuffle
  import numpy
  import os
  from caserec.recommenders.rating_prediction.itemknn import ItemKNN
  from caserec.recommenders.rating_prediction.matrixfactorization import MatrixFactorization
  from caserec.recommenders.rating_prediction.svdplusplus import SVDPlusPlus
  from caserec.recommenders.rating_prediction.userknn import UserKNN
  from caserec.utils.process_data import ReadFile
  from caserec.utils.extra_functions import ComputeBui
label_desc: Use image node_id 17 for calling the ECoRec obj's underlying member method code with example usage: obj.transform_dict(list_to_transform) and returns: new_dict