your response for more than 2 weeks.

**4. Approved**

-   Once the PR is approved, it gets `kokoro:force-run` label applied and it
    initiates CI/CD tests.
-   We can't move forward if these tests fail.
-   In such situations, we may request you to make further changes to your PR
    for the tests to pass.
-   Once the tests pass, we now bring all the code into the internal code base,
    using a job called "copybara".

  if [[ -s $BATS_TEST_TMPDIR/actual_missing_licenses ]]; then
    echo "Please include the missing licenses for the following packages in $LICENSES_TARGET:"
    cat $BATS_TEST_TMPDIR/actual_missing_licenses
  fi

  # Fail if either of the two "extras" or "missing" lists are present. If so,
  # then the user will see the above error messages.
  [[ ! -s $BATS_TEST_TMPDIR/actual_extra_licenses ]] && [[ ! -s $BATS_TEST_TMPDIR/actual_missing_licenses ]]
}

  auto pop_call_state = gtl::MakeCleanup([this] { this->call_state_.pop(); });

  std::vector<Gradient*> forward_grads;
  if (forward_function == nullptr) {
    // We have no special-cased forward gradient. Fall back to running the
    // backward function under a gradient tape.
    forward_grads.resize(output_tensors.size());
    TF_RETURN_IF_ERROR(ForwardpropFromTape(
        op_type, output_tensors, backward_function_getter,