code: def validate(self, name: str, obj):
      super().validate(name, obj)
      for k, v in obj.items():
          if not isinstance(k, str):
              raise ValidationError(f"{name} has non-str key")
          self.vchecker.validate(f"{name}[{k}]", v)
  
imports: from typing import Union, Dict, Pattern, Callable, Any, List, Optional
  import re
  import logging
label_desc: Use image node_id 2 for calling the DictValidator obj's underlying member method code with example usage: obj.validate(name, obj) without return types