code: def source():
      return ColumnDataSource(
          dict(x=[1, 2, 3], y=[1, 2, 3], label=["a", "b", "c"])
      )
  
imports: from __future__ import annotations
  import pytest
  import re
  import pandas
  from bokeh.core.enums import MarkerType
  from bokeh.core.properties import value
  from bokeh.models import BoxZoomTool, Circle, ColumnDataSource, LassoSelectTool, Legend, LinearAxis, LogScale, PanTool, ResetTool, Scatter, Title
  from bokeh.util.warnings import BokehDeprecationWarning
  from bokeh.plotting import _figure
label_desc: Use image node_id 3 for calling a global function with example usage: source() and returns: ColumnDataSource