code: def setPathCheck(key):
      """check if path exist"""
      return And(os.path.exists, error=SCHEMA_PATH_ERROR % key)
  
imports: import json
  import os
  from schema import And, Optional, Or, Regex, Schema, SchemaError
  from nni.tools.package_utils.tuner_factory import create_validator_instance
  from .common_utils import get_yml_content, print_warning
  from .constants import SCHEMA_PATH_ERROR, SCHEMA_RANGE_ERROR, SCHEMA_TYPE_ERROR
label_desc: Use image node_id 4 for calling a global function with example usage: setPathCheck(key) and returns: And