dist/scripts/vendor.min.js
function getSetDayOfWeek (input) {
        var day = this._isUTC ? this._d.getUTCDay() : this._d.getDay();
        if (input != null) {
            input = parseWeekday(input, this.localeData());
            return this.add(input - day, 'd');
        } else {
            return day;
        }
    }
function getSetDayOfWeek (input) {
        var day = this._isUTC ? this._d.getUTCDay() : this._d.getDay();
        if (input != null) {
            input = parseWeekday(input, this.localeData());
            return this.add(input - day, 'd');
        } else {
            return day;
        }
    }
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