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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 _extract_service_catalog(self, body):
 """Set the client's service catalog from the response data."""

        self.auth_ref = access.create(body=body)
        self.service_catalog = self.auth_ref.service_catalog
        self.auth_token = self.auth_ref.auth_token
        self.auth_tenant_id = self.auth_ref.tenant_id
        self.auth_user_id = self.auth_ref.user_id

        if not self.endpoint_url:
            self.endpoint_url = self.service_catalog.url_for(
                region_name=self.region_name,
                service_type=self.service_type,
                interface=self.endpoint_type)