code: def test_struct_supertype() -> None:
      assert pl.from_dicts(
          [{"vehicle": {"auto": "car"}}, {"vehicle": {"auto": None}}]
      ).to_dict(as_series=False) == {
          "vehicle": [{"auto": "car"}, {"auto": None}]
      }
  
imports: from __future__ import annotations
  from dataclasses import dataclass
  from datetime import datetime, time
  from typing import TYPE_CHECKING
  import pandas
  import pyarrow
  import pytest
  import polars
  import polars.selectors
  from polars.testing import assert_frame_equal, assert_series_equal
label_desc: Use image node_id 31 for calling a global function with example usage: test_struct_supertype() without return types