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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def _render_picking(self, **kwargs):
 """Render the scene in picking mode, returning a 2D array of visual IDs. """

        try:
            self._scene.picking = True
            img = self.render(bgcolor=(0, 0, 0, 0), **kwargs)
        finally:
            self._scene.picking = False
        img = img.astype('int32') * [2**0, 2**8, 2**16, 2**24]
        id_ = img.sum(axis=2).astype('int32')
        return id_