How to use the react-calendar/build/shared/dates.getMonthIndex function in react-calendar

'use strict';

Object.defineProperty(exports, "__esModule", {
  value: true
});
exports.getISOLocalDate = exports.getISOLocalMonth = exports.getMonth = exports.getEnd = exports.getBegin = exports.getDaysInMonth = exports.getDay = exports.getMonthIndex = exports.getYear = undefined;

var _dates = require('react-calendar/build/shared/dates');

exports.getYear = _dates.getYear;
exports.getMonthIndex = _dates.getMonthIndex;
exports.getDay = _dates.getDay;
exports.getDaysInMonth = _dates.getDaysInMonth;
exports.getBegin = _dates.getBegin;
exports.getEnd = _dates.getEnd;

/* Simple getters - getting a property of a given point in time */

var getMonth = exports.getMonth = function getMonth(date) {
  return date.getMonth() + 1;
};

/* Complex getters - getting a property somehow related to a given point in time */

/**
 * Returns local month in ISO-like format (YYYY-MM).
 */