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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 transposable_node(self, parent=None, tag='g', attrib=None, **extras):
 """Make a new svg node which can be transposed if horizontal"""

        if self.graph.horizontal:
            for key1, key2 in (('x', 'y'), ('width', 'height'), ('cx', 'cy')):
                attr1 = extras.get(key1, None)
                attr2 = extras.get(key2, None)
                if attr2:
                    extras[key1] = attr2
                elif attr1:
                    del extras[key1]
                if attr1:
                    extras[key2] = attr1
                elif attr2:
                    del extras[key2]
        return self.node(parent, tag, attrib, **extras)