docs: def send_verification_mail(request, user, verification_type):
      """
      Sends an email with a verification link to users when
      ``ACCOUNTS_VERIFICATION_REQUIRED`` is ```True`` and they're signing
      up, or when they reset a lost password.
      The ``verification_type`` arg is both the name of the urlpattern for
      the verification link, as well as the names of the email templates
      to use.
      """
      verify_url = reverse(verification_type, kwargs={
          "uidb36": int_to_base36(user.id),
          "token": default_token_generator.make_token(user),
      }) + "?next=" + (next_url(request) or "/")
      context = {
          "request": request,
          "user": user,
          "verify_url": verify_url,
      }
      subject_template_name = "email/%s_subject.txt" % verification_type
      subject = subject_template(subject_template_name, context)
      send_mail_template(subject, "email/%s" % verification_type,
                         settings.DEFAULT_FROM_EMAIL, user.email,
                         context=context)