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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 roles(self):
 """gets the roles class that allows admins to manage custom roles on portal"""

        return Roles(url="%s/roles" % self.root,
                     securityHandler=self._securityHandler,
                     proxy_url=self._proxy_url,
                     proxy_port=self._proxy_port)