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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 next_sibling(self):
 """The next sibling statement node. :returns: The next sibling statement node. :rtype: NodeNG or None """

        stmts = self.parent.child_sequence(self)
        index = stmts.index(self)
        try:
            return stmts[index + 1]
        except IndexError:
            pass