text: from django.db import models
  from django.db.models import fields
  
  from django_react_chat_example_project.users.models import User
  
  
  def get_chat_users_queryset():
      return User.objects.all()
  
  
  class ChatGroup(models.Model):
      users = models.ManyToManyField(User)
  
  
  class ChatMessage(models.Model):
      text = fields.TextField()
      author = models.ForeignKey(User)
      chat_group = models.ForeignKey(ChatGroup, on_delete=models.CASCADE, related_name="messages")
  