GET(url) {
            return fetch(
                url,
                {headers: {'Accept': 'application/json'}}
            ).then(response => {
                if (response.ok) {
                    return response.json()
                }
                return [];
            });
        }

        function sendPOST(url, data) {
            return fetch(url, {
                method: 'POST',
                headers: {'Content-Type': 'application/json'},
                body: JSON.stringify(data)
    