code: def project_drawn(cb, msg):
      
      stream = cb.streams[0]
      old_data = stream.data
      stream.update(data=msg['data'])
      element = stream.element
      stream.update(data=old_data)
      proj = cb.plot.projection
      if not isinstance(element, _Element) or element.crs == proj:
          return None
      crs = element.crs
      element.crs = proj
      return project(element, projection=crs)
docs: Projects a drawn element to the declared coordinate system