Getting a "Is Not a Function" Error While Running a Test (Javascript, Cypress)

below is my code and when I run my test it comes up as months is not a function. This is for a cypress test. Any idea where I am going wrong?

class DateUtils {
  getMonthIndexFromName(monthName) {
    months = {
      January: '1',
      Febuary: '2',
      March: '3',
      April: '4',
      May: '5',
      June: '6',
      July: '7',
      August: '8',
      September: '9',
      October: '10',
      Novemebr: '11',
      December: '12',
    };
    return months(monthName);
  }
}
export default DateUtils;