text: """Realise deferred functions."""
  from account.models import User
  from celery import shared_task
  from django.conf import settings
  from django.core.mail import send_mail
  
  
  @shared_task
  def send_activation_link_mail(user_id):
      """Activation link."""
      user = User.objects.get(id=user_id)
      link = settings.DOMAIN + "/activate/" + str(user.confirmation_token)
      msg = f"Activation link {link}"
      send_mail(
          "Super Space Blog: Activate your account",
          msg,
          settings.DEFAULT_FROM_EMAIL,
          [user.email],
          fail_silently=False
      )
  