django 1.8 error: 'NoneType' object is not callable

Please see in picture, there is a form with 2 fields. After user entry the information and submit the form. The page will redirect to another html showing the form AND the filtered database result.

The structure of my project is 1 model with 2 classes(inputform; result), 2 html and 1 views.py.

The issue now is "'NoneType' object is not callable'. So I suspect it is because the views.py , there is something wrong. Your help is really appreciated. Thanks in advance.

url

from result.views import ResultView,InputFormView
from django.views.generic import TemplateView,FormView,ListView

urlpatterns = patterns('',    
    url(r'^result_list/$',ResultView.as_view(),name='result'),
    url(r'^input/$',InputFormView.as_view(),name='input'), 
)

views.py

from result.forms import InputForm
from result.models import Result,Input
from django.views.generic.list import ListView
from django.views.generic import FormView
....

@csrf_exempt

class InputFormView(FormView):
    template_name = 'inputform.html'
    form = InputForm

    def get_success_url(self):  /*redirect to result page with submitted form information*/
        return ''.join(
            [
                reverse('dupont'),
                '?company=',self.request.POST.get('company'),
                '?region=',self.request.POST.get('region')
            ]
        )

class ResultView(ListView):
    context_object_name = 'result_list'
    template_name = 'result_list.html'

    def get_context_data(self, **kwargs):
        context = super(ResultView, self).get_context_data(**kwargs)
        return context

    def get_queryset(self):
        if self.request.method == 'POST':
            form = InputForm(self.request.POST)
            if form.is_valid():
                company = form.cleaned_data['company']
                region = form.cleaned_data['region']

/---Based on form entry, do the filter on the database-----/

                queryset=Result.objects.filter(region=region,company=company)
                sales=Result.objects.filter(queryset).aggregate(Sum('sales'))
                employee=Result.objects.filter(queryset).aggregate(Sum('employee'))
                departments=Result.objects.filter(queryset).aggregate(Sum('departments'))

                form.save()

                return render(request,'result_list.html',{'company':company},{'region':region},{'employee':employee},{'sales':sales},{'departments':departments})

            else:
                print form.errors
        else:
            form=InputForm()                   
        return super(ResultView,self).get_queryset()

Traceback:

    File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\core\handlers\base.py" in get_response
132.                     response = wrapped_callback(request, *callback_args, **callback_kwargs)
    File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\base.py" in view
71.             return self.dispatch(request, *args, **kwargs)
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\base.py" in dispatch
89.         return handler(request, *args, **kwargs)
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\edit.py" in get
205.         form = self.get_form()
File "C:\Python27\lib\site-packages\django-1.8.3-py2.7.egg\django\views\generic\edit.py" in get_form
74.         return form_class(**self.get_form_kwargs())
Exception Type: TypeError at /input/
Exception Value: 'NoneType' object is not callable

result_list.html

<div class="basicinfo">         <!--Entry Form information submitted by user-->

    <table border="1" cellpadding="1">
    <tr>
        <td align="left">Company</td>
        <td>{{ company }}</td>
    </tr>
    <tr>
        <td align="left">Region</td>
        <td>{{ region }}</td>
    </tr>
  </table>
{% endfor %}
</div>     

<!--Showing the filtered result in database-->  
<td><table border="0" cellspacing="10" cellpadding="10">
<tr><b>Sales</b></tr>
<td bgcolor="#F0F0F0"> {{sales}}</td>

</tr>
<tr><b>Employee</b></tr>
<tr>
<td bgcolor="#F0F0F0"> {{employee.employee__sum}}</td>

</tr>
<tr><b>Departments</b></tr>
<td bgcolor="#F0F0F0"> {{departments.departments__sum}}</td>
</td></table>

input.html

<div class="field">
        {{ form.company.errors }}
        <label for="{{ form.company.id_for_label }}">Company:</label>
        {{ form.company }}
</div>

<div class="field" >
<label> Select the Region:
    {{ form.region }}
        {% for region in form.region.choices %}
        <option value="region" name= "region" id="id_region">{{region}} </option>
        {% endfor %}
</label>
</div>

Upgraded views.py based on suggestion

from result.forms import InputForm
from django.views.generic import DetailView
from django.views.generic.edit import FormView,FormMixin
from django.contrib import messages
from django.template import RequestContext
from django.shortcuts import redirect
from django.db.models import Sum,Avg
from django.views.generic.detail import MultipleObjectMixin

class InputFormView(FormMixin,DetailView):
    template_name = 'inputform.html'
    form = InputForm

    def post(self, request, *args, **kwargs):
        self.object = self.get_object()
        form=self.get_form()
        if form.is_valid():
            return self.form_valid(form)
        else:
            return self.form_invalid(form)
            print form.errors

    def get(self, request, *args, **kwargs):
        view = DupontView.as_view()
        return view(request, *args, **kwargs)

    def form_valid(self, form):
        company = form.cleaned_data['company']
        region = form.cleaned_data['region']

        queryset=Result.objects.filter(company=company,region=region)
        sales=Result.objects.queryset.aggregate(Sum('sales'))
        employee=Result.objects.queryset.aggregate(Sum('employee'))
        departments=Result.objects.queryset.aggregate(Sum('departments'))

        return super(ResultView,self).form_valid(form)

    def get_success_url(self):
        return reverse('dupont', kwargs={'pk': self.object.pk})

class ResultView(MultipleObjectMixin,DetailView):
    context_object_name = 'result_list'
    template_name = 'result_list.html'


    <----how can I get the submitted information and query result here from InputFormView? Is following correct?--->

    def get(self, request, *args, **kwargs):
        self.object = self.get_object(queryset=Result.objects.filter(company=company,region=region))            
        return super(Result, self).get(request, *args, **kwargs)

    def get_context_data(self, **kwargs):
        context = super(ResultView, self).get_context_data(**kwargs)
        context['InputFormView']= self.object
        return context

    def get_queryset(self):
        return self.object. ? .all()  <---what to put here? are they  "sales","departments","employee" from database filtered result together with the form data-"region" and "company"?