如何在mongoose中找到具有相同值的字段？

const mongoose = require('mongoose');

// 定义模式和模型
const Schema = mongoose.Schema;
const mySchema = new Schema({
  field: String
});
const MyModel = mongoose.model('MyModel', mySchema);

// 在mongoose中找到具有相同值的字段
MyModel.aggregate([
  {
    $group: {
      _id: "$field",
      count: { $sum: 1 },
      documents: { $push: "$$ROOT" }
    }
  },
  {
    $match: {
      count: { $gt: 1 }
    }
  }
])
.exec((err, result) => {
  if (err) {
    console.error(err);
    return;
  }
  console.log(result);
});