code: def __init__(self):
      super(PanZoomTransform, self).__init__()
      self._pan = None
      self._zoom = None
  
imports: import numpy
  import math
  from vispy import gloo, app, scene
  from vispy.visuals import Visual
  from vispy.visuals.shaders import Function, Variable
  from vispy.visuals.transforms import TransformSystem, BaseTransform
  from vispy.util.profiler import Profiler
label_desc: Use image node_id 1 to create a new PanZoomTransform object from inherited base classes: BaseTransform with example: obj = PanZoomTransform()