@extract_id(User)<EOL><INDENT>def permanently_delete(self, user):<DEDENT>
url = self._build_url(self.endpoint.deleted(id=user))<EOL>deleted_user = self._delete(url)<EOL>self.cache.delete(deleted_user)<EOL>return deleted_user<EOL>
Permanently delete user. User should be softly deleted first.
Zendesk API `Reference <https://developer.zendesk.com/rest_api/docs/core/users#permanently-delete-user>`__.

Note: This endpoint does not support multiple ids or list of `User` objects.

:param user: User object or id.
:return: User object with `permanently_deleted` status