code: def mock_ecr():
      """Mock an instance of the ECR class."""
      ecr = MagicMock()
  
file_path: wandb/tests/pytest_tests/unit_tests_old/test_launch/test_launch_aws.py
imports: import json
  import sys
  from unittest.mock import MagicMock
  import pytest
  import wandb
  import wandb.sdk.launch._launch
  import wandb.sdk.launch._project_spec
  from wandb.sdk.launch.environment.aws_environment import AwsEnvironment
  from wandb.sdk.launch.errors import LaunchError
  from wandb.sdk.launch.runner.sagemaker_runner import SagemakerSubmittedRun
  from tests.pytest_tests.unit_tests_old.utils import fixture_open
  from .test_launch import mocked_fetchable_git_repo
label_desc: Use image node_id 2 for calling a global function with example usage: mock_ecr() without return types