text: const mongoose  = require("mongoose");
  const Schema = mongoose.Schema;
  
  //create an exercise schema for mongoDb
  
  const exerciseSchema = new Schema({
      username: { type: String, required: true },
      description: { type: String, required: true },
      duration: { type: Number, required: true },
      date: {type: Date, required: true},
  },
  {
      timestamps: true
  
  });
  
  const Exercise = mongoose.model('Exercise', exerciseSchema);
  
  module.exports = Exercise;