我尝试添加markup并清理输入，但一直收到错误;这是我的密码

const mongoose = require('mongoose');
const slug = require('slugify');
const createDomPurify = require('dompurify');
const marked = require('marked');
const {JSDOM} = require('jsdom');
const dompurify = createDomPurify( new JSDOM().window);

const CPASchema = {
   

   //SOME PART OF THIS CODE BUT UNNECESSARY TO THE QUESTION 

    answer:{
        type:String
    },

    sanitizedHTML:{
        type: String,
        required: true
    }
}

CPASchema.pre('validate', async function(data, next){ 

    if(data.answer) {
         console.log('JUST BEFORE SANITIZING')
        data.sanitizedHTML = await dompurify.sanitize(marked(data.answer));
    }
    next()

})

module.exports = mongoose.model('CPASchema', CPASchema);

这是我一直收到的错误

CPASchema.pre('validate', async function(data, next){
          ^

TypeError: CPASchema.pre is not a function

编辑我已尝试更改mongoose版本，但没有帮助