code: def test_unknown_map_elements() -> None:
      df = pl.DataFrame(
          {
              "Amount": [10, 1, 1, 5],
              "Flour": ["1000g", "100g", "50g", "75g"],
          }
      )
  
      q = df.lazy().select(
          [
              pl.col("Amount"),
              pl.col("Flour").map_elements(lambda x: 100.0)
              / pl.col("Amount"),
          ]
      )
  
      assert q.collect().to_dict(as_series=False) == {
          "Amount": [10, 1, 1, 5],
          "Flour": [10.0, 100.0, 100.0, 20.0],
      }
      assert q.dtypes == [pl.Int64, pl.Unknown]
  
imports: from __future__ import annotations
  from collections import OrderedDict
  from datetime import date, timedelta
  from typing import Any, Iterator, Mapping
  import pytest
  import polars
  from polars.testing import assert_frame_equal, assert_series_equal
label_desc: Use image node_id 13 for calling a global function with example usage: test_unknown_map_elements() without return types