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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 wsfed_metadata(self):
 """Returns the WS-Federation Metadata. """


        url = 'https://{}/wsfed/FederationMetadata' \
              '/2007-06/FederationMetadata.xml'

        return self.get(url=url.format(self.domain))