code: def __iter__(self):
      if self.sampling_mode == "link":
          self.lib.initTest()
          return TestDataSampler(self.testTotal, self.sampling_lp)
      else:
          self.lib.initTest()
          return TestDataSampler(1, self.sampling_tc)
  
imports: import os
  import ctypes
  import numpy
label_desc: Use image node_id 10 for calling the TestDataLoader obj's underlying member method code with example usage: obj.__iter__() and returns: TestDataSampler, TestDataSampler