code: def test_df_describe_empty_column() -> None:
      df = pl.DataFrame(schema={"a": pl.Int64})
  
      result = df.describe()
  
      expected = pl.DataFrame(
          [
              ("count", 0.0),
              ("null_count", 0.0),
              ("mean", None),
              ("std", None),
              ("min", None),
              ("25%", None),
              ("50%", None),
              ("75%", None),
              ("max", None),
          ],
          schema=["describe"] + df.columns,
      )
      assert_frame_equal(result, expected)
  
file_path: polars/py-polars/tests/unit/dataframe/test_describe.py
imports: from __future__ import annotations
  from datetime import date
  import pytest
  import polars
  from polars.testing import assert_frame_equal
label_desc: Use image node_id 5 for calling a global function with example usage: test_df_describe_empty_column() without return types