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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 add_text_structure(self, label):
 """ Adds a citable text structure to the work. """


        ts = self.session.get_resource("%s/text_structure" % self.subject
                                      , self.session.get_class(surf.ns.HUCIT['TextStructure']))
        ts.rdfs_label.append(Literal(label))
        ts.save()
        self.hucit_has_structure = ts
        self.update()
        return self.hucit_has_structure.one