class_docstr: Per-stream handler of EventListener gRPC streams.
class_docstr_tok: ["Per-stream","handler","of","EventListener","gRPC","streams","."]
docstr: Callback for core metadata.
  
  Args:
    event: The Event proto that carries a JSON string in its
      `log_message.message` field.
  
  Returns:
    `None` or an `EventReply` proto to be sent back to the client. If `None`,
    an `EventReply` proto construct with the default no-arg constructor will
    be sent back to the client.
docstr_tok: ["Callback","for","core","metadata",".","Args",":","event",":","The","Event","proto","that","carries","a","JSON","string","in","its","`","log_message.message","`","field",".","Returns",":","`","None","`","or","an","`","EventReply","`","proto","to","be","sent","back","to","the","client",".","If","`","None","`",",","an","`","EventReply","`","proto","construct","with","the","default","no-arg","constructor","will","be","sent","back","to","the","client","."]
code: def on_core_metadata_event(self, event):
      """Callback for core metadata.
  
      Args:
        event: The Event proto that carries a JSON string in its
          `log_message.message` field.
  
      Returns:
        `None` or an `EventReply` proto to be sent back to the client. If `None`,
        an `EventReply` proto construct with the default no-arg constructor will
        be sent back to the client.
      """
      raise NotImplementedError(
          "on_core_metadata_event() is not implemented in the base servicer "
          "class"
      )
  
imports: import collections
  import json
  import queue
  import threading
  import time
  from concurrent import futures
  import grpc
  from tensorflow.core.debug import debug_service_pb2
  from tensorflow.core.framework import graph_pb2
  from tensorflow.python.debug.lib import debug_graphs
  from tensorflow.python.debug.lib import debug_service_pb2_grpc
  from tensorflow.python.platform import tf_logging
  from tensorflow.python.util import compat
label_desc: Use image node_id 2 for calling the EventListenerBaseStreamHandler obj's underlying member method code with example usage: obj.on_core_metadata_event(event) without return types