code: def test_time_validate_value_none():
      t = datetime.datetime(2002, 2, 20, 13, 37, 42, 7)
      t_min = datetime.datetime(1442, 1, 1)
      t_max = datetime.datetime(2056, 1, 1)
      w = NaiveDatetimePicker(value=t, min=t_min, max=t_max)
      w.value = None
      assert w.value is None
  
file_path: catboost/contrib/python/ipywidgets/py3/ipywidgets/widgets/tests/test_widget_naive_datetime.py
imports: import pytest
  import datetime
  import pytz
  from traitlets import TraitError
  from ..widget_datetime import NaiveDatetimePicker
label_desc: Use image node_id 3 for calling a global function with example usage: test_time_validate_value_none() without return types