code: def testKnown(self):
      num_elements = 10
      ds = dataset_ops.Dataset.range(num_elements)
      self.assertLen(ds, 10)
  
file_path: tensorflow-upstream/tensorflow/python/data/kernel_tests/len_test.py
imports: from absl.testing import parameterized
  from tensorflow.python.data.kernel_tests import test_base
  from tensorflow.python.data.ops import dataset_ops
  from tensorflow.python.framework import combinations
  from tensorflow.python.platform import test
label_desc: Use image node_id 1 for calling the LenTest obj's underlying member method code with example usage: obj.testKnown() without return types