code: def test_time_to_string_cast() -> None:
      assert pl.Series([time(12, 1, 1)]).cast(str).to_list() == [
          "12:01:01"
      ]
  
imports: from datetime import time
  import polars
label_desc: Use image node_id 1 for calling a global function with example usage: test_time_to_string_cast() without return types