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'use strict';
const addAutoId = require('./addAutoId');
module.exports = function handleIdOption(schema, options) {  if (options == null || options._id == null) {    return schema;  }
  schema = schema.clone();  if (!options._id) {    schema.remove('_id');    schema.options._id = false;  } else if (!schema.paths['_id']) {    addAutoId(schema);    schema.options._id = true;  }
  return schema;};