title: Django Sending Email Using Signals
body: <p>I'm testing django signal to send an email but I'm getting the following error.</p>
  
  <p>'list' object has no attribute 'splitlines'</p>
  
  <pre><code>@receiver(post_save, sender=Booking)
  
  def new_booking(sender, instance, **kwargs):
  if instance.firstname:
      firstname = [instance.firstname]
      # lastname = [instance.lastname]
      email = [instance.email]
      # phone = [instance.phone]
      subject = [instance.service]
      # date = [instance.date]
      # time = [instance.time]
      # fullname = [firstname + lastname]
      # details = [service]
      send_mail(firstname, subject, email,
                ['cmadiam@abc.com'], fail_silently=False)
  </code></pre>
  
  <p>Do i miss something?</p>
  
  <p>Thanks again!</p>