code: def to_var(self, x, use_gpu):
      if use_gpu:
          return Variable(torch.from_numpy(x).cuda())
      else:
          return Variable(torch.from_numpy(x))
  
imports: import torch
  import torch.nn
  from torch.autograd import Variable
  import torch.optim
  import os
  import time
  import sys
  import datetime
  import ctypes
  import json
  import numpy
  from sklearn.metrics import roc_auc_score
  import copy
  from tqdm import tqdm
label_desc: Use image node_id 5 for calling the Tester obj's underlying member method code with example usage: obj.to_var(x, use_gpu) and returns: Variable, Variable