code: def _normalize(self, vec):
      return vec / vec.sum()
  
imports: from absl.testing import parameterized
  import numpy
  from tensorflow.python.compat import compat
  from tensorflow.python.data.kernel_tests import checkpoint_test_base
  from tensorflow.python.data.kernel_tests import test_base
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.data.ops import options
  from tensorflow.python.eager import def_function
  from tensorflow.python.framework import combinations
  from tensorflow.python.framework import errors
  from tensorflow.python.framework import ops
  from tensorflow.python.framework import random_seed
  from tensorflow.python.platform import test
label_desc: Use image node_id 1 for calling the SampleFromDatasetsTest obj's underlying member method code with example usage: obj._normalize(vec) and returns: unknown