code: def __iter__(self):
      return SampleIterator(iter(self.src), self.is_multioutput)
  
imports: import functools
  import numpy
  import nvidia.dali.fn
  import nvidia.dali.ops
  from nvidia.dali import Pipeline
  from nose_utils import assert_raises
  from test_utils import check_output
label_desc: Use image node_id 2 for calling the SampleIterator obj's underlying member method code with example usage: obj.__iter__() and returns: SampleIterator