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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 _need_subquery(arg, attributes, named_attributes):
 """ Decide whether the projection argument needs to be wrapped in a subquery """

        if arg.heading.expressions or arg.distinct:  # argument has any renamed (computed) attributes
            return True
        restricting_attributes = arg.attributes_in_restriction()
        return (not restricting_attributes.issubset(attributes) or  # if any restricting attribute is projected out or
                any(v.strip() in restricting_attributes for v in named_attributes.values()))