from common.models import LinesModel class LineFilterFormMixin: def get_form(self, form_class=None): form = super().get_form(form_class) user = self.request.user if user.line: form.fields['line'].queryset = form.fields['line'].queryset.filter(pk=user.line.pk) form.fields['line'].initial = user.line form.fields['line'].widget.attrs['readonly'] = True else: form.fields['line'].queryset = LinesModel.objects.filter(company=user.company) form.fields['line'].widget.attrs['readonly'] = False return form