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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 oaiset_url(self):
 """Return the OAISet URL for given community. :returns: URL of corresponding OAISet. :rtype: str """

        return url_for(
            'invenio_oaiserver.response',
            verb='ListRecords',
            metadataPrefix='oai_dc', set=self.oaiset_spec, _external=True)