Extend django-registration to send HTML emails for activation

gistfile1.py

class HtmlRegistrationProfile(RegistrationProfile):
    class Meta:
        proxy = True
    def send_activation_email(self, site):
        """Send the activation mail"""
        from django.core.mail import EmailMultiAlternatives
        from django.template.loader import render_to_string

        ctx_dict = {'activation_key': self.activation_key,
                    'expiration_days': settings.ACCOUNT_ACTIVATION_DAYS,
                    'site': site}
        subject = render_to_string('registration/activation_email_subject.txt',
                                   ctx_dict)
        # Email subject *must not* contain newlines
        subject = ''.join(subject.splitlines())

        message_text = render_to_string('registration/activation_email.txt', ctx_dict)
        message_html = render_to_string('registration/activation_email.html', ctx_dict)

        msg = EmailMultiAlternatives(subject, message_text, settings.DEFAULT_FROM_EMAIL, [self.user.email])
        msg.attach_alternative(message_html, "text/html")
        msg.send()