class_docstr: Registers metrics with XManager.
class_docstr_tok: ["Registers","metrics","with","XManager","."]
code: def __init__(self):
      super(tf.keras.callbacks.Callback, self).__init__()
      self.xm_client = xmanager_api.XManagerApi()
      self.work_unit = self.xm_client.get_current_work_unit()
  
imports: import gc
  import os
  import re
  from typing import Any, Dict, Optional, Tuple
  import warnings
  from absl import app
  from absl import flags
  from absl import logging
  from ml_collections.config_flags import config_flags
  import tensorflow
  import tensorflow_addons
  from deepvariant import data_providers
  from deepvariant import dv_constants
  from deepvariant import dv_utils
  from deepvariant import keras_modeling
  from deepvariant.average_model_checkpoint_patched import AverageModelCheckpointPatched
  from third_party.nucleus.io import sharded_file_utils
  from official.modeling import optimization
label_desc: Use image node_id 1 to create a new XManagerCallback object from inherited base classes: tf.keras.callbacks with example: obj = XManagerCallback()