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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 get(self, id):
 """Retrieves custom domain. See: https://auth0.com/docs/api/management/v2#!/Custom_Domains/get_custom_domains_by_id """

        url = self._url('%s' % (id))
        return self.client.get(url)