Get all token types that an address owns
        Returns {'tokens': [...]}

def GET_account_tokens(self, path_info, account_addr):
        """
        Get all token types that an address owns
        Returns {'tokens': [...]}
        """
        if not check_account_address(account_addr):
            return self._reply_json({'error': 'Invalid address'}, status_code=400)

        blockstackd_url = get_blockstackd_url()
        res = blockstackd_client.get_account_tokens(account_addr, hostport=blockstackd_url)
        if json_is_error(res):
            log.error("Failed to load tokens for {}: {}".format(account_addr, res['error']))
            return self._reply_json({'error': 'Failed to load tokens for {}: {}'.format(account_addr, res['error'])}, status_code=res.get('http_status', 500))

        self._reply_json({'tokens': res})
        return