code: def test_group_by_double_on_empty_12194() -> None:
      df = pl.DataFrame({"group": [1], "x": [1]}).clear()
      squared_deviation_sum = (
          (pl.col("x") - pl.col("x").mean()) ** 2
      ).sum()
      assert df.group_by("group").agg(
          squared_deviation_sum
      ).schema == OrderedDict([("group", pl.Int64), ("x", pl.Float64)])
  
imports: from __future__ import annotations
  from collections import OrderedDict
  from datetime import datetime, timedelta
  from typing import Any
  import pytest
  import polars
  from polars.testing import assert_frame_equal, assert_series_equal
label_desc: Use image node_id 36 for calling a global function with example usage: test_group_by_double_on_empty_12194() without return types