class_docstr: Class for adding callouts to the chart.
code: def __init__(self, chart):
      self._chart = chart
  
file_path: chartify/chartify/_core/callout.py
imports: import bokeh
  from chartify._core import colors
  from chartify._core.axes import DatetimeXNumericalYAxes
label_desc: Use image node_id 1 to create a new Callout object  with example: obj = Callout(chart)