code: def _resolve_matrix_data(self) -> Dict[str, List]:
      try:
          iterable = self.context.resolve(
              self.matrix_data, unwrap=False
          )
      except (ContextError, ParseError) as exc:
          format_and_raise(
              exc, f"'{self.where}.{self.name}.matrix'", self.relpath
          )
  
      # Matrix entries will have `key` and `item` added to the context.
      # Warn users if these are already in the context from the global vars.
      self._warn_if_overwriting([self.pair.key, self.pair.value])
      return iterable
  
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 4 for calling the MatrixDefinition obj's underlying member method code with example usage: obj._resolve_matrix_data() and returns: iterable