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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 visualize(self, format='svg'):
 """Visualize an expression in the browser as an SVG image. Parameters format : str, optional Defaults to ``'svg'``. Some additional formats are ``'jpeg'`` and ``'png'``. These are specified by the ``graphviz`` Python library. Notes ----- This method opens a web browser tab showing the image of the expression graph created by the code in :module:`ibis.expr.visualize`. Raises ------ ImportError If ``graphviz`` is not installed. """

        import ibis.expr.visualize as viz

        path = viz.draw(viz.to_graph(self), format=format)
        webbrowser.open('file://{}'.format(os.path.abspath(path)))