code: def _read_data() -> dict[tuple[State, County], float]:
      """ """
      data: dict[tuple[State, County], float] = {}
      with open_csv(external_path("unemployment09.csv")) as f:
          reader = csv.reader(f, delimiter=",", quotechar='"')
          for row in reader:
              _, state_id, county_id, _, _, _, _, _, rate = row
              data[(int(state_id), int(county_id))] = float(rate)
      return data
  
imports: from __future__ import annotations
  import logging
  import csv
  from typing import TYPE_CHECKING
  from ..util.sampledata import external_path, open_csv
label_desc: Use image node_id 1 for calling a global function with example usage: _read_data() and returns: data