Python-сообщество

class Context(models.Model): 
    name        = models.CharField(unique=True)

class ContextForm(forms.ModelForm): 
    name = forms.CharField() 
    class Meta: 
        model = Context

form = ContextForm(request.POST) 
... 
if form.is_valid(): 
    form.save()

class ContextForm(forms.ModelForm): 
    name = forms.CharField(error_messages={'unique': u'Контекст с 
таким именем уже существует') 
    class Meta: 
        model = Context