code: def test_correctness(self):
      interpolation_times = [
          1.0,
          3.0,
          6.0,
          7.0,
          8.0,
          15.0,
          18.0,
          25.0,
          30.0,
      ]
  
      reference_times = [0.0, 2.0, 6.0, 8.0, 18.0, 30.0]
      reference_yields = [0.01, 0.02, 0.015, 0.014, 0.02, 0.025]
      result = self.evaluate(
          constant_fwd_interpolation.interpolate(
              interpolation_times, reference_times, reference_yields
          )
      )
      expected_result = np.array(
          [
              0.02,
              0.0175,
              0.015,
              0.01442857,
              0.014,
              0.01904,
              0.02,
              0.0235,
              0.025,
          ]
      )
      np.testing.assert_allclose(result, expected_result, atol=1e-6)
  
file_path: tf-quant-finance/tf_quant_finance/rates/constant_fwd/constant_fwd_interpolation_test.py
imports: from absl.testing import parameterized
  import numpy
  import tensorflow.compat.v2
  from tensorflow.python.framework import test_util
  from tf_quant_finance.rates.constant_fwd import constant_fwd_interpolation
label_desc: Use image node_id 1 for calling the ConstantFwdInterpolationTest obj's underlying member method code with example usage: obj.test_correctness() without return types