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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 url_for(self, operation, _external=True, **kwargs):
 """ Construct a URL for an operation against a resource. :param kwargs: additional arguments for URL path expansion, which are passed to flask.url_for. In particular, _external=True produces absolute url. """

        return url_for(self.endpoint_for(operation), _external=_external, **kwargs)