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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 visit_AugAssign(self, node):
 """ Update range value for augassigned variables. Interval(low=1, high=2) """

        self.generic_visit(node)
        if isinstance(node.target, ast.Name):
            name = node.target.id
            res = combine(node.op,
                          self.result[name],
                          self.result[node.value])
            self.result[name] = self.result[name].union(res)