code: def test_histogram_datetime64_plot(self):
      dates = np.array([dt.datetime(2017, 1, i) for i in range(1, 5)])
      hist = histogram(Dataset(dates, "Date"), num_bins=4)
      plot = bokeh_renderer.get_plot(hist)
      source = plot.handles["source"]
      data = {
          "top": np.array([1, 1, 1, 1]),
          "left": np.array(
              [
                  "2017-01-01T00:00:00.000000",
                  "2017-01-01T18:00:00.000000",
                  "2017-01-02T12:00:00.000000",
                  "2017-01-03T06:00:00.000000",
              ],
              dtype="datetime64[us]",
          ),
          "right": np.array(
              [
                  "2017-01-01T18:00:00.000000",
                  "2017-01-02T12:00:00.000000",
                  "2017-01-03T06:00:00.000000",
                  "2017-01-04T00:00:00.000000",
              ],
              dtype="datetime64[us]",
          ),
      }
      for k, v in data.items():
          self.assertEqual(source.data[k], v)
      xaxis = plot.handles["xaxis"]
      range_x = plot.handles["x_range"]
      self.assertIsInstance(xaxis, DatetimeAxis)
      self.assertEqual(
          range_x.start,
          np.datetime64("2017-01-01T00:00:00.000000", "us"),
      )
      self.assertEqual(
          range_x.end, np.datetime64("2017-01-04T00:00:00.000000", "us")
      )
  
imports: import datetime
  import numpy
  from bokeh.models import CategoricalColorMapper, DatetimeAxis, LinearColorMapper
  from holoviews.core.overlay import NdOverlay
  from holoviews.element import Dataset, Histogram, Image, Points
  from holoviews.operation import histogram
  from holoviews.plotting.bokeh.util import property_to_dict
  from ...utils import LoggingComparisonTestCase
  from .test_plot import TestBokehPlot, bokeh_renderer
label_desc: Use image node_id 4 for calling the TestSideHistogramPlot obj's underlying member method code with example usage: obj.test_histogram_datetime64_plot() without return types