python - How to update model's field Django from form with save method? -

i'm trying update model's fields save method:

forms.py:

class fooform(forms.modelform):     class meta:         model = foo         exclude = ['created'] 

views.py:

class fooview(formview):     success_url = '/some/url/'     template_name = 'some/template.html'     form_class = fooform     model = foo      def form_valid(self, form):         if 'foo' in self.request.session:             pk = self.request.session['foo']             foo = foo.objects.get(pk=pk)             self.object = form.save(instance=foo)         else:             self.object = form.save()             self.request.session['foo'] = self.object.pk         return httpresponseredirect(self.get_success_url()) 

i have error, when try use form.save(instance=foo):

typeerror @ /some/url save() got unexpected keyword argument 'instance' 

what problem?

django 1.9.0

python 3.4.3

if read documentation linked, see instance keyword input modelform constructor , not save method.

you need like

form = fooform(instance=foo) form.save()