django - Create a query to database from the data in form -

my code

#model.py class personal(models.model):     name = models.charfield(db_column='fio', max_length=255, blank=true, null=true)     history_contract = models.charfield(max_length=255, blank=true, null=true)     category = models.charfield(max_length=255, blank=true, null=true)  #form.py class nameform(forms.form):     name = forms.charfield(label='name', max_length=100)     history_contract = forms.charfield(label='history', max_length=100)     category = forms.charfield(label='category', max_length=100)  #view def get_personal(request):     if request.method == 'post':         form = nameform(request.post)         if form.is_valid():             name = form.cleaned_data['name']#data form             history = form.cleaned_data['history_contract']#data form             category = form.cleaned_data['category']#//data form             query = sotrudniki.objects.filter(fio__contain=name, history_contract__contain=history, category__contain=category)#the part want accomplish      else:         form = nameform()     return render(request, 'personal.html', {'form': form, 'query': query}) 

i need check data entered form. after making request database , returning data indicated in form. got error @ end "local variable 'query' referenced before assignment", maybe have wrong approach task. how can implement idea?

this simple logic error. query not exist when form not post, try , send template anyway. can fix putting query = none @ beginning of function.