how to make link in email clickable to register form in django code example

Example: User signup with email, mobile, name, password fields using email confirmation django

from django.http import HttpResponse
from django.shortcuts import render, redirect
from django.contrib.auth import login, authenticate
from .forms import SignupForm
from django.contrib.sites.shortcuts import get_current_site
from django.utils.encoding import force_bytes, force_text
from django.utils.http import urlsafe_base64_encode, urlsafe_base64_decode
from django.template.loader import render_to_string
from .tokens import account_activation_token
from django.contrib.auth.models import User
from django.core.mail import EmailMessage
def signup(request):    
  if request.method == 'POST':        
    form = SignupForm(request.POST)        
    if form.is_valid():            
      user = form.save(commit=False)            
      user.is_active = False            
      user.save()            
      current_site = get_current_site(request)            
      mail_subject = 'Activate your blog account.'            
      message = render_to_string('acc_active_email.html', {                
        'user': user,                
        'domain': current_site.domain,                
        'uid':urlsafe_base64_encode(force_bytes(user.pk)),                
        'token':account_activation_token.make_token(user),            
      })            
      to_email = form.cleaned_data.get('email')            
      email = EmailMessage(mail_subject, message, to=[to_email])            
      email.send()            
      return HttpResponse('Please confirm your email address to complete the registration')    
    else:        
      form = SignupForm()    
      return render(request, 'signup.html', {'form': form})