Javascript和chart.js，如何在y标签中添加欧元货币

var ctx = document.getElementById('myChart').getContext('2d');
var myChart = new Chart(ctx, {
    type: 'bar',
    data: {
        labels: ['January', 'February', 'March', 'April', 'May', 'June', 'July'],
        datasets: [{
            label: 'Sales',
            data: [1000, 2000, 1500, 3000, 2500, 1800, 4000],
            backgroundColor: 'rgba(0, 123, 255, 0.5)'
        }]
    },
    options: {
        scales: {
            yAxes: [{
                ticks: {
                    callback: function(value, index, values) {
                        return value.toLocaleString('de-DE', { style: 'currency', currency: 'EUR' });
                    }
                }
            }]
        }
    }
});