class_docstr: Tests for Heston Price method.
code: def test_docstring(self, dtype):
      prices = tff.models.heston.approximations.european_option_price(
          variances=0.11,
          strikes=102.0,
          expiries=1.2,
          forwards=100.0,
          is_call_options=True,
          mean_reversion=2.0,
          theta=0.5,
          volvol=0.15,
          rho=0.3,
          discount_factors=1.0,
          dtype=dtype,
      )
      # Computed using scipy
      self.assertAllClose(prices, 24.822196, rtol=1e-5, atol=1e-5)
  
file_path: tf-quant-finance/tf_quant_finance/models/heston/approximations/european_option_test.py
imports: from absl.testing import parameterized
  import numpy
  import tensorflow.compat.v2
  import tf_quant_finance
  from tensorflow.python.framework import test_util
label_desc: Use image node_id 1 for calling the HestonPriceTest obj's underlying member method code with example usage: obj.test_docstring(dtype) without return types