code: def validate_test(
      test: Test, schema: Optional[Dict] = None
  ) -> Optional[str]:
      schema = schema or load_schema_file()
  
      try:
          jsonschema.validate(test, schema=schema)
      except (jsonschema.ValidationError, jsonschema.SchemaError) as e:
          return str(e.message)
      except Exception as e:
          return str(e)
  
imports: import copy
  import json
  import os
  import re
  from typing import Dict, List, Optional, Tuple, Any
  import jsonschema
  import yaml
  from ray_release.test import Test, TestDefinition
  from ray_release.anyscale_util import find_cloud_by_name
  from ray_release.bazel import bazel_runfile
  from ray_release.exception import ReleaseTestCLIError, ReleaseTestConfigError
  from ray_release.logger import logger
  from ray_release.util import DeferredEnvVar, deep_update
label_desc: Use image node_id 6 for calling a global function with example usage: validate_test(test, schema) and returns: str, str