code: def panzoom(marks):
      
      return PanZoom(scales={
              'x': sum([mark._get_dimension_scales('x', preserve_domain=True) for mark in marks], []),
              'y': sum([mark._get_dimension_scales('y', preserve_domain=True) for mark in marks], [])
      })
docs: Helper function for panning and zooming over a set of marks.
  
      Creates and returns a panzoom interaction with the 'x' and 'y' dimension
      scales of the specified marks.