parameters: (self, event)
docstring: 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.
docstring_summary: Callback for core metadata.
docstring_tokens: Callback for core metadata .
function: 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")
function_tokens: def on_core_metadata_event ( self , event ) : raise NotImplementedError ( "on_core_metadata_event() is not implemented in the base servicer " "class" )