How to use the moment.localeData function in moment

import React from 'react';
import PropTypes from 'prop-types';

import moment from 'moment';
import { translateUsingPseudoLocale } from '../../../src/services/string/pseudo_locale_translator';

// For testing/demoing EuiDatePicker, process moment's `en` locale config into a babelfished version
const enConfig = moment.localeData('en')._config;
moment.defineLocale('en-xa', {
  ...enConfig,
  months: enConfig.months.map(translateUsingPseudoLocale),
  monthsShort: enConfig.monthsShort.map(translateUsingPseudoLocale),
  weekdays: enConfig.weekdays.map(translateUsingPseudoLocale),
  weekdaysMin: enConfig.weekdaysMin.map(translateUsingPseudoLocale),
  weekdaysShort: enConfig.weekdaysShort.map(translateUsingPseudoLocale),
});
// Reset default moment locale after using `defineLocale`
moment.locale('en');

import { EuiSwitch, EuiFormRow } from '../../../../src/components';

export const GuideLocaleSelector = ({ selectedLocale, onToggleLocale }) => {
  return (

getLocalizedDateFormat(localizedFormat: any): string {
        return moment.localeData().longDateFormat(localizedFormat);
    }

value() {
            return (
              (Nuxeo.UI && Nuxeo.UI.config && parseInt(Nuxeo.UI.config.firstDayOfWeek, 10)) ||
              moment.localeData().firstDayOfWeek() ||
              0
            );
          },
          observer: '_firstDayOfWeekChanged',

export function getLocaleDataForLocale (locale) {
  return moment.localeData(locale)
}

      { getFirstDayOfWeek: () => moment.localeData().firstDayOfWeek() },
    );

firstOfWeek: function firstOfWeek(culture: string) {
      return (moment.localeData(culture) as any).firstDayOfWeek();
    },

i18n: function() {
      return moment.localeData(this.props.locale) ||
             moment.localeData(defaultProps.locale);
  },

isLastDayOfWeek(day) {
    const { firstDayOfWeek } = this.props;
    return day.day() === ((firstDayOfWeek || moment.localeData().firstDayOfWeek()) + 6) % 7;
  }

  displayFormat: () => moment.localeData().longDateFormat('L'),

public render() {
    const { current, locale } = this.props;

    const dayMatrix = getDayMatrix(current.year(), current.month());
    const weekdays = moment.localeData(locale).weekdaysShort();

    return (
       (
          
        )}
      />