How to use the web.Dialog function in web

_show_help: function() {
        var buttons = [{
            text: _t("Ok"),
            close: true,
        }];
    	var dialog = new Dialog(this, {
            size: 'medium',
            buttons: buttons,
            $content: $(QWeb.render('muk_dms.DocumentHelpDialogContent')),
            title: _t("Help"),
        });
    	dialog.open();
    },
});

.done(function (fields) {
                new Dialog(self, {
                    title: _.str.sprintf(_t("Fields of %s"), model),
                    $content: $(QWeb.render('WebClient.DebugManager.Action.Fields', {
                        fields: fields
                    }))
                }).open();
            });
    },

.fail(function (err, data) {
            return new Dialog(self, {
                title: data.data ? data.data.arguments[0] : "",
                $content: $('<div>', {
                    html: (data.data ? data.data.arguments[1] : data.statusText)
                        + '<br>'
                        + _.str.sprintf(
                            _t('It might be possible to edit the relevant items or fix the issue in <a href="%s">the classic Flectra interface</a>'),
                            '/web#return_label=Website&amp;model=' + $data.data('object') + '&amp;id=' + $data.data('id')
                        ),
                }),
            }).open();
        });
    },</div>

_onChangeLayout: function (event) {
        var self = this;
        var dialog = new Dialog(this, {
            title: _t("Edit Layout"),
            $content: QWeb.render('DashBoard.layouts', _.clone(event.data))
        });
        dialog.opened().then(function () {
            dialog.$('li').click(function () {
                var layout = $(this).attr('data-layout');
                self.renderer.changeLayout(layout);
                self._saveDashboard();
                dialog.close();
            });
        });
        dialog.open();
    },

fvg: function() {
        var self = this;
        var dialog = new Dialog(this, { title: _t("Fields View Get") });
        dialog.opened().then(function () {
            $('<pre>').text(utils.json_node_to_xml(
                self._controller.renderer.arch, true)
            ).appendTo(dialog.$el);
        });
        dialog.open();
    },
});</pre>