code: def test_nested_enum_creation() -> None:
      dtype = pl.List(pl.Enum(["a", "b", "c"]))
      s = pl.Series([[None, "a"], ["b", "c"]], dtype=dtype)
      assert s.len() == 2
      assert s.dtype == dtype
  
imports: import operator
  from datetime import date
  from textwrap import dedent
  from typing import Any, Callable
  import pytest
  import polars
  from polars import StringCache
  from polars.testing import assert_series_equal
label_desc: Use image node_id 5 for calling a global function with example usage: test_nested_enum_creation() without return types