text: from django.db.models.signals import m2m_changed
  from django.dispatch import receiver
  
  from .models import Image
  
  
  @receiver(m2m_changed, sender=Image.users_like_for_img.through)
  def users_like_changed(sender, instance, **kwargs):
      """
          There's some concept I haven't grasped yet.
          
          Note
              1. Django 'signals' are blocking (that means you CAN'T do async stuff!)
              
      """
      
      instance.total_likes = instance.users_like_for_img.count()
      instance.save()