JS: access variable defined in parent method inside mixin method

I’m writing a mixin for vendor/magento/module-checkout/view/frontend/web/js/sidebar.js
I need to add extra events to

       _initContent: function () {
            var self = this,
                events = {};

            this.element.decorate('list', this.options.isRecursive);

            /**
             * @param {jQuery.Event} event
             */
            events['click ' + this.options.button.close] = function (event) {
                event.stopPropagation();
                $(self.options.targetElement).dropdownDialog('close');
            };
            events['click ' + this.options.button.checkout] = $.proxy(function () {
                var cart = customerData.get('cart'),
                    customer = customerData.get('customer'),
                    element = $(this.options.button.checkout);

                if (!customer().firstname && cart().isGuestCheckoutAllowed === false) {
                    // set URL for redirect on successful login/registration. It's postprocessed on backend.
                    $.cookie('login_redirect', this.options.url.checkout);

                    if (this.options.url.isRedirectRequired) {
                        element.prop('disabled', true);
                        location.href = this.options.url.loginUrl;
                    } else {
                        authenticationPopup.showModal();
                    }

                    return false;
                }
                element.prop('disabled', true);
                location.href = this.options.url.checkout;
            }, this);
...

            this._on(this.element, events);
            this._calcHeight();
        },

but inside a mixin I can’t access the events object

define([
    'jquery'
], function ($) {
    'use strict';
    return function (widget) {

        $.widget('mage.sidebar', widget, {
            
        _initContent: function () {
            this._super();

            /**
             * @param {jQuery.Event} event
             */
            events['click ' + '.minicart-items-wrapper .qty-increase'] = function (event) {
                console.log('increase')
            };

            /**
             * @param {jQuery.Event} event
             */
            events['click ' + '.minicart-items-wrapper .qty-decrease'] = function (event) {
                console.log('decrease');
            };

            this._on(this.element, events);
        },


        });

        return $.mage.sidebar;
    };
});

it says events is not defined