std::vector<AbstractTensorHandle*> outputs;
  int expected_num_outputs = -1;
};

namespace tracing {

// =============================================================================
// Implementation detail for the unified execution APIs for Eager and tracing
// backends (graph/MLIR).
//
// This defines a set of abstract classes that are intended to provide the

  //
  // The given `name` must be parseable by DeviceNameUtils::ParseFullName, and
  // the result will be used as a constraint for device placement. See the
  // documentation for DeviceName for more details.
  //
  // The value will override the previous value - that is, no "merging" of
  // existing and given constraints will be performed.
  virtual Status SetDeviceName(const char* name) = 0;