TapeContext::~TapeContext() {
  // TODO(srbs): Make AbstractContext ref counted.
  // parent_ctx_->Unref();
}
TapeOperation* TapeContext::CreateOperation() {
  return new TapeOperation(parent_ctx_->CreateOperation(), tape_, registry_);
}
Status TapeContext::RegisterFunction(AbstractFunction* f) {
  return parent_ctx_->RegisterFunction(f);
}
Status TapeContext::RemoveFunction(const string& func) {
  return parent_ctx_->RemoveFunction(func);
}

#include "tensorflow/c/eager/abstract_context.h"
#include "tensorflow/c/experimental/gradients/tape/tape_operation.h"

namespace tensorflow {
namespace gradients {
class TapeContext : public AbstractContext {
 public:
  explicit TapeContext(AbstractContext*, Tape*, const GradientRegistry&);
  void Release() override;
  TapeOperation* CreateOperation() override;
  Status RegisterFunction(AbstractFunction*) override;

    Tape tape(/*persistent=*/false);
    for (size_t i{}; i < inputs.size(); ++i) {
      tape.Watch(inputs[i]);
    }
    std::vector<AbstractTensorHandle*> temp_outputs(1);
    AbstractContextPtr tape_ctx(new TapeContext(ctx, &tape, grad_registry));
    TF_RETURN_IF_ERROR(
        forward_model(tape_ctx.get(), inputs, absl::MakeSpan(temp_outputs)));

    TF_RETURN_IF_ERROR(tape.ComputeGradient(ctx, /*targets=*/temp_outputs,