code: def test_make_iso_8601_datetime(self, install_temp):
      # GH#21199
      import checks
  
      dt = datetime(2016, 6, 2, 10, 45, 19)
      # uses NPY_FR_s
      result = checks.make_iso_8601_datetime(dt)
      assert result == b"2016-06-02T10:45:19"
  
imports: from datetime import datetime
  import os
  import shutil
  import subprocess
  import sys
  import time
  import pytest
  import numpy
  from numpy.testing import IS_WASM
label_desc: Use image node_id 1 for calling the TestDatetimeStrings obj's underlying member method code with example usage: obj.test_make_iso_8601_datetime(install_temp) without return types