code: def test_lengths_ops(self):
      LengthsTester()._test(
          "Lengths",
          hu.lengths_tensor(
              dtype=np.float32,
              min_value=1,
              max_value=5,
              allow_empty=True,
          ),
          REFERENCES_ALL + REFERENCES_LENGTHS_ONLY,
      )(self)
  
imports: from functools import partial
  from hypothesis import given, settings
  import numpy
  import unittest
  import hypothesis.strategies
  from caffe2.python import core, workspace
  import caffe2.python.hypothesis_test_util
  import caffe2.python.serialized_test.serialized_test_util
label_desc: Use image node_id 6 for calling the TestSegmentOps obj's underlying member method code with example usage: obj.test_lengths_ops() without return types