code: def _has_group_and_key(self, group: str, key: Optional[str] = None):
      try:
          definition = self.definitions[group]
      except KeyError:
          return False
  
      if not isinstance(
          definition, (ForeachDefinition, MatrixDefinition)
      ):
          return key is None
      return key is not None and definition.has_member(key)
  
imports: import logging
  import os
  from collections.abc import Mapping, Sequence
  from copy import deepcopy
  from itertools import product
  from typing import TYPE_CHECKING, Any, Dict, List, NamedTuple, Optional, Tuple, Type, Union
  from funcy import collecting, first, isa, join, reraise
  from dvc.exceptions import DvcException
  from dvc.log import logger
  from dvc.parsing.interpolate import ParseError
  from dvc.utils.objects import cached_property
  from .context import Context, ContextError, KeyNotInContext, MergeError, Node, VarsAlreadyLoaded
  from .interpolate import check_recursive_parse_errors, is_interpolated_string, recurse, to_str
label_desc: Use image node_id 5 for calling the DataResolver obj's underlying member method code with example usage: obj._has_group_and_key(group, key) and returns: unknown, unknown, False