code: def generate_image_uri():
      """Returns unique name+tag for a Docker image."""
      # Keeping this name format uniform with the job id.
      unique_tag = str(uuid.uuid4()).replace("-", "_")
      docker_registry = "gcr.io/{}".format(gcp.get_project_name())
      return "{}/{}:{}".format(
          docker_registry, "tf_cloud_train", unique_tag
      )
  
imports: import logging
  import os
  import sys
  import tarfile
  import tempfile
  import time
  import uuid
  import warnings
  from .None import gcp
  from .None import machine_config
  import docker
  from google.cloud import storage
  from google.cloud.exceptions import NotFound
  from googleapiclient import discovery
  from googleapiclient import errors
  import requests
  from ..utils import google_api_client
  from ..utils import tf_utils
label_desc: Use image node_id 1 for calling a global function with example usage: generate_image_uri() and returns: str