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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 create(fmt):
 """ Creates a GraphRenderer """

        w = None
        if fmt == 'tree':
            w = AsciiTreeGraphRenderer()
        elif fmt == 'dot':
            w = DotGraphRenderer(image_format='dot')
        elif fmt == 'png':
            w = DotGraphRenderer(image_format='png')
        elif fmt == 'ndot':
            w = NativeDotGraphRenderer()
        elif fmt == 'obo':
            w = OboFormatGraphRenderer()
        elif fmt == 'obog':
            w = OboJsonGraphRenderer()
        else:
            w = SimpleListGraphRenderer()
        return w