code: def _get_size_data(self, element, ranges, style):
      data, mapping = {}, {}
      sdim = element.get_dimension(self.size_index)
      ms = style.get("size", np.sqrt(6))
      if sdim and (
          (isinstance(ms, str) and ms in element) or isinstance(ms, dim)
      ):
          self.param.warning(
              "Cannot declare style mapping for 'size' option and "
              "declare a size_index; ignoring the size_index."
          )
          sdim = None
      if not sdim or self.static_source:
          return data, mapping
  
      map_key = "size_" + sdim.name
      ms = ms**2
      sizes = element.dimension_values(self.size_index)
      sizes = compute_sizes(
          sizes,
          self.size_fn,
          self.scaling_factor,
          self.scaling_method,
          ms,
      )
      if sizes is None:
          eltype = type(element).__name__
          self.param.warning(
              f"{sdim.pprint_label} dimension is not numeric, cannot use to scale {eltype} size."
          )
      else:
          data[map_key] = np.sqrt(sizes)
          mapping["size"] = map_key
      return data, mapping
  
imports: from collections import defaultdict
  import numpy
  import param
  from bokeh.models import CategoricalColorMapper, CustomJS, FactorRange, Range1d, Whisker
  from bokeh.models.tools import BoxSelectTool
  from bokeh.transform import jitter
  from ...core.data import Dataset
  from ...core.dimension import dimension_name
  from ...core.util import dimension_sanitizer, isfinite
  from ...operation import interpolate_curve
  from ...util.transform import dim
  from ..mixins import AreaMixin, BarsMixin, SpikesMixin
  from ..util import compute_sizes, get_min_distance
  from .element import ColorbarPlot, ElementPlot, LegendPlot, OverlayPlot
  from .selection import BokehOverlaySelectionDisplay
  from .styles import base_properties, expand_batched_style, fill_properties, line_properties, mpl_to_bokeh, rgb2hex
  from .util import categorize_array
label_desc: Use image node_id 1 for calling the PointPlot obj's underlying member method code with example usage: obj._get_size_data(element, ranges, style) and returns: data,  mapping, data,  mapping