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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_Call(self, node):
 """ Function calls are not handled for now. Interval(low=-inf, high=inf) """

        for alias in self.aliases[node.func]:
            if alias is MODULES['__builtin__']['getattr']:
                attr_name = node.args[-1].s
                attribute = attributes[attr_name][-1]
                self.add(node, attribute.return_range(None))
            elif isinstance(alias, Intrinsic):
                alias_range = alias.return_range(
                    [self.visit(n) for n in node.args])
                self.add(node, alias_range)
            else:
                return self.generic_visit(node)
        return self.result[node]