code: def metric_mock():
      mock = MagicMock()
      mock.record.return_value = "haha"
      yield mock
  
imports: import signal
  import json
  import os
  import pathlib
  import sys
  import requests
  from pprint import pformat
  from unittest.mock import MagicMock
  import numpy
  import pytest
  import ray
  from ray.util.state import list_nodes
  from ray._private.metrics_agent import PrometheusServiceDiscoveryWriter
  from ray._private.ray_constants import PROMETHEUS_SERVICE_DISCOVERY_FILE
  from ray._private.test_utils import SignalActor, fetch_prometheus, fetch_prometheus_metrics, get_log_batch, wait_for_condition, raw_metrics
  from ray.autoscaler._private.constants import AUTOSCALER_METRIC_PORT
  from ray.dashboard.consts import DASHBOARD_METRIC_PORT
  from ray.util.metrics import Counter, Gauge, Histogram
label_desc: Use image node_id 8 for calling a global function with example usage: metric_mock() without return types