code: def chart_pie():
      return pv.ChartPie([1, 2, 3])
  
imports: import itertools
  import platform
  import weakref
  import numpy
  import pytest
  from vtkmodules.vtkRenderingContext2D import vtkPen
  import pyvista
  from pyvista import examples
  from pyvista.plotting import charts
  from pyvista.plotting.colors import COLOR_SCHEMES
label_desc: Use image node_id 7 for calling a global function with example usage: chart_pie() and returns: pv