docs: SchemaHelper is not exported from core rather than knex?

[Clex1o1]

Hi there! In the documentation I found the section about custom driver. It tells me to implement a Schema class which extended the SchemaHelper class: https://mikro-orm.io/docs/custom-driver#schemahelper

import { SchemaHelper } from '@mikro-orm/core';

export class MyCustomSchemaHelper extends SchemaHelper {

SchemeHelper is not exported from @mikro-orm/core but I found it in the knex package. Should the documentation be corrected to install the knex package and import the class from it? Or did I miss something im my setup?