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'use strict';
const get = require('../get');
module.exports = function isDefaultIdIndex(index) {  if (Array.isArray(index)) {    // Mongoose syntax    const keys = Object.keys(index[0]);    return keys.length === 1 && keys[0] === '_id' && index[0]._id !== 'hashed';  }
  if (typeof index !== 'object') {    return false;  }
  const key = get(index, 'key', {});  return Object.keys(key).length === 1 && key.hasOwnProperty('_id');};