class_docstr: Specialized PolyCollection for arrows.
  
  The only API method is set_UVC(), which can be used
  to change the size, orientation, and color of the
  arrows; their locations are fixed when the class is
  instantiated.  Possibly this method will be useful
  in animations.
  
  Much of the work in this class is done in the draw()
  method so that as much information as possible is available
  about the plot.  In subsequent draw() calls, recalculation
  is limited to things that might have changed, so there
  should be no performance penalty from putting the calculations
  in the draw() method.
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code: def get_datalim(self, transData):
      trans = self.get_transform()
      offset_trf = self.get_offset_transform()
      full_transform = (trans - transData) + (offset_trf - transData)
      XY = full_transform.transform(self.XY)
      bbox = transforms.Bbox.null()
      bbox.update_from_data_xy(XY, ignore=True)
      return bbox
  
imports: import math
  import numpy
  from numpy import ma
  from matplotlib import _api, cbook, _docstring
  import matplotlib.artist
  import matplotlib.collections
  from matplotlib.patches import CirclePolygon
  import matplotlib.text
  import matplotlib.transforms
label_desc: Use image node_id 3 for calling the Quiver obj's underlying member method code with example usage: obj.get_datalim(transData) and returns: bbox