FCM token for Django project (Firebase) -- 2

Django project with a User Model , there are 3 types of users (Admin,Teacher and Parent) each user has his Mobile Application with flutter , need Rest API for the mobile app. The API must include - use a stable fcm django library well documented (we can discuss this) - save the token for each user in the database - send a notifications to a group of users (ex: type==teacher) - send a notification to a specific user - can send a notification with a list of users at one time (not create a notification for each user) to not take a lot of time to send the notification from the server Solution work with django version :Django 1.11 MySQL