Copies the turtle data from the old shape buffer to the new

def set_shape(self, id, new_shape):
        """Copies the turtle data from the old shape buffer to the new"""
        old_shape = self.id_to_shape[id]
        old_buffer = self.get_buffer(old_shape)
        model, color = old_buffer.get(id)
        new_data = self._create_turtle(id, new_shape, model, color)
        old_buffer.remove(id)
        self.id_to_shape[id] = new_shape
        return new_data