docstr: Tests that double_factorial generates expected results.
docstr_tok: ["Tests","that","double_factorial","generates","expected","results","."]
code: def test_double_factorial_preset(self, test_inputs, test_outputs):
      """Tests that double_factorial generates expected results."""
      self.assert_output_is_correct(
          math_helpers.double_factorial, test_inputs, test_outputs
      )
  
imports: import sys
  from absl.testing import parameterized
  import numpy
  import tensorflow
  from tensorflow_graphics.math import math_helpers
  from tensorflow_graphics.util import asserts
  from tensorflow_graphics.util import test_case
label_desc: Use image node_id 7 for calling the MathTest obj's underlying member method code with example usage: obj.test_double_factorial_preset(test_inputs, test_outputs) without return types