code: def test_Whisker() -> None:
      whisker = Whisker()
      assert whisker.level == "underlay"
      assert whisker.lower == field("lower")
      assert whisker.lower_units == "data"
      assert isinstance(whisker.lower_head, ArrowHead)
      assert whisker.lower_head.size == 10
      assert whisker.upper == field("upper")
      assert whisker.upper_units == "data"
      assert isinstance(whisker.upper_head, ArrowHead)
      assert whisker.upper_head.size == 10
      assert whisker.base == field("base")
      assert whisker.dimension == "height"
      assert isinstance(whisker.source, ColumnDataSource)
      assert whisker.x_range_name == "default"
      assert whisker.y_range_name == "default"
      check_line_properties(whisker, "")
      check_properties_existence(
          whisker,
          [
              *ANNOTATION,
              "lower",
              "lower_units",
              "lower_head",
              "upper",
              "upper_units",
              "upper_head",
              "base",
              "base_units",
              "dimension",
              "source",
          ],
          LINE,
      )
  
imports: from __future__ import annotations
  import pytest
  from datetime import datetime
  from unittest import mock
  from bokeh.core.properties import field, value
  from bokeh.core.validation import check_integrity, process_validation_issues
  from bokeh.models import Arrow, ArrowHead, Band, BoxAnnotation, ColorBar, ColumnDataSource, GlyphRenderer, Label, LabelSet, Legend, LegendItem, LinearColorMapper, Node, PolyAnnotation, Slope, Span, Title, Whisker
  from bokeh.util.serialization import convert_datetime_type
  from _util_models import ABOVE_FILL, ABOVE_HATCH, ANGLE, BELOW_FILL, BELOW_HATCH, FILL, HATCH, HOVER_FILL, HOVER_HATCH, HOVER_LINE, LINE, TEXT, check_fill_properties, check_hatch_properties, check_line_properties, check_properties_existence, check_text_properties, prefix
label_desc: Use image node_id 17 for calling a global function with example usage: test_Whisker() without return types