code: def non_reducing_slice(slice_: Subset):
      """
      Ensure that a slice doesn't reduce to a Series or Scalar.
  
      Any user-passed `subset` should have this called on it
      to make sure we're always working with DataFrames.
      """
      # default to column slice, like DataFrame
      # ['A', 'B'] -> IndexSlices[:, ['A', 'B']]
      kinds = (ABCSeries, np.ndarray, Index, list, str)
      if isinstance(slice_, kinds):
          slice_ = IndexSlice[:, slice_]
  
      def pred(part) -> bool:
          """
          Returns
          -------
          bool
              True if slice does *not* reduce,
              False if `part` is a tuple.
          """
          # true when slice does *not* reduce, False when part is a tuple,
          # i.e. MultiIndex slice
          if isinstance(part, tuple):
              # GH#39421 check for sub-slice:
              return any(
                  (isinstance(s, slice) or is_list_like(s))
                  for s in part
              )
          else:
              return isinstance(part, slice) or is_list_like(part)
  
      if not is_list_like(slice_):
          if not isinstance(slice_, slice):
              # a 1-d slice, like df.loc[1]
              slice_ = [[slice_]]
          else:
              # slice(a, b, c)
              slice_ = [slice_]  # to tuplize later
      else:
          # error: Item "slice" of "Union[slice, Sequence[Any]]" has no attribute
          # "__iter__" (not iterable) -> is specifically list_like in conditional
          slice_ = [p if pred(p) else [p] for p in slice_]  # type: ignore[union-attr]
      return tuple(slice_)
  
imports: from __future__ import annotations
  from collections import defaultdict
  from functools import partial
  import re
  from typing import Any, Callable, DefaultDict, Dict, List, Optional, Sequence, Tuple, TypedDict, Union
  from uuid import uuid4
  import numpy
  from pandas._config import get_option
  from pandas._libs import lib
  from pandas._typing import Axis, Level
  from pandas.compat._optional import import_optional_dependency
  from pandas.core.dtypes.common import is_complex, is_float, is_integer
  from pandas.core.dtypes.generic import ABCSeries
  from pandas import DataFrame, Index, IndexSlice, MultiIndex, Series, isna
  from pandas.api.types import is_list_like
  import pandas.core.common
  from markupsafe import escape
label_desc: Use image node_id 11 for calling a global function with example usage: non_reducing_slice(slice_) and returns: tuple, any, unknown