Error at /contact/ -- [Errno 111] Connection refused (in the djangobook , chapter 7: Forms)

Question

I get this error while I was learning Django from examples in djangobook (chapter 7 - Forms).

Full error:
error at /contact/

[Errno 111] Connection refused

Request Method:     POST
Request URL:    http://localhost:8000/contact/
Django Version:     1.8.4
Exception Type:     error
Exception Value:    

[Errno 111] Connection refused

Exception Location:     /usr/lib/python2.7/socket.py in create_connection, line 571
Python Executable:  /usr/bin/python
Python Version:     2.7.6

Here is the code:

views.py

def contact(request):
    if request.method == 'POST':
        form = ContactForm(request.POST)
        if form.is_valid():
            cd = form.cleaned_data
            send_mail(
                cd['subject'],
                cd['message'],
                cd.get('email', '[email protected]'),
                ['[email protected]'],
            )
            return HttpResponseRedirect('/contact/thanks/')
    else:
        form = ContactForm()
    return render(request, 'contact_form.html', {'form': form})

Please resolve this error. Thanks.