mbmohib

def clean(self):
        try:
            User.objects.get(first_name=self.cleaned_data['first_name'],
                             last_name=self.cleaned_data['last_name'])
            raise forms.ValidationError("Exists already!")
        except User.DoesNotExist:
            pass
        return self.cleaned_data

mbmohib

def clean_email(self):
        email = self.cleaned_data.get('email')
        username = self.cleaned_data.get('username')
        if email and User.objects.filter(
                email=email).exclude(username=username).count():
            raise forms.ValidationError(
                "A user with that email already exists")
        return email

mbmohib

# Three methods of getting object's url:


<a href='/posts/{{ post.id }}'><p>{{ post.title }}</p></a> (#static)

<a href='{% url 'detail' id=post.id %}'><p>{{ post.title|title }}</p></a>

<a href='{{ post.get_absolute_url }}'><p>{{ post.title|title }}</p></a>