try {
    await mongoose.connect(
      'mongodb+srv://...........cluster0-ua4e7.mongodb.net/todos',
      {
        useNewUrlParser: true,
        useFindAndModify: false
      }
    )
    app.listen(PORT, () => {
      console.log('Server has been started...')
    })
  } catch (e) {
    console.log(e)
  }