class_docstr: Interface for the head/top of a ranking model.
class_docstr_tok: ["Interface","for","the","head\/top","of","a","ranking","model","."]
docstr: Constructor. See `create_ranking_head`.
docstr_tok: ["Constructor",".","See","`","create_ranking_head","`","."]
code: def __init__(
      self,
      loss_fn,
      eval_metric_fns=None,
      optimizer=None,
      train_op_fn=None,
      name=None,
  ):
      """Constructor. See `create_ranking_head`."""
      self._loss_fn = loss_fn
      self._eval_metric_fns = eval_metric_fns or {}
      self._optimizer = optimizer
      self._train_op_fn = train_op_fn
      self._name = name
  
imports: from __future__ import absolute_import
  from __future__ import division
  from __future__ import print_function
  import abc
  import six
  import tensorflow
  from tensorflow import estimator
label_desc: Use image node_id 1 to create a new _RankingHead object from inherited base classes: _AbstractRankingHead with example: obj = _RankingHead(loss_fn, eval_metric_fns, optimizer, train_op_fn, name)