code: def series_of_str_dates() -> pl.Series:
      return pl.Series(
          [
              "2020-01-01 00:00:00.000000000",
              "2020-02-02 03:20:10.987654321",
          ]
      )
  
imports: from __future__ import annotations
  import sys
  from datetime import date, datetime, time, timedelta
  from typing import TYPE_CHECKING
  import pytest
  import polars
  from polars.datatypes import DTYPE_TEMPORAL_UNITS
  from polars.dependencies import _ZONEINFO_AVAILABLE
  from polars.exceptions import ComputeError, InvalidOperationError
  from polars.testing import assert_frame_equal, assert_series_equal
label_desc: Use image node_id 2 for calling a global function with example usage: series_of_str_dates() and returns: pl