Django Ajax post 500 internal error -

i hope can me, im trying make django post form without reloading page using ajax, im getting error 500 when submit, can me fix this, code:

models.py

class productoconcepto(models.model):     producto = models.foreignkey(producto)     orden = models.foreignkey(cobro)     cantidad = models.floatfield() 

urls.py

from django.conf.urls import patterns, include, url django.contrib import admin cobro import views  urlpatterns = [     url(r'^cobro/agregar_concepto/$', views.addconcept_product, name='add_concepto'), ] 

views.py

def addconcept_product(request):      if request.method == 'post':          if form.is_valid():             producto = request.post['producto']             orden = request.post['orden']             cantidad = request.post['cantidad']              productoconcepto.objects.create(producto=producto, orden=orden, cantidad=cantidad)              return httpresponse('') 

template

    <div class="modal inmodal fade" id="mymodal1" tabindex="-1" role="dialog"  aria-hidden="true">             <div class="modal-dialog modal-m">                 <div class="modal-content">                     <div class="modal-header">                         <button type="button" class="close" data-dismiss="modal">                             <span aria-hidden="true">&times;</span>                             <span class="sr-only">cerrar</span>                         </button>                         <h3 class="modal-title">agregar nuevo concepto</h3>                     </div>                     <div class="modal-body">                         <p>datos de concepto agregar:</p>                         <div class="doctorformstyle">                         <form id='formulario-modal' method='post' enctype='multipart/form-data'>                             {% csrf_token %}                             <ul>{{form2.as_p}}</ul>  <!--  rendered form2 fields: <select id="id_producto" name="producto"><option value="1" selected="selected">object</option></select> --> <!--  form2 fields: <select id="id_orden" name="orden"> <option value="1" selected="selected">object</option> </select> --> <!--  form2 fields: <input id="id_cantidad" name="cantidad" step="any" type="number"> -->                              <div class="row align-center">                                 <input type='submit' name="save1" value='guardar' class="btn btn-w-m btn-primary"/>                             </div>                          </form> </div>                     </div>                 </div>             </div>         </div>  <script type="text/javascript">     $(document).on('submit', '#formulario-modal', function(e){             e.preventdefault();             $.ajax ({                 type: 'post',                 url: '{% url 'add_concepto' %}',                 data: {                     producto: $('#id_producto').val(),                     orden: $('#id_orden').val(),                     cantidad: $('#id_cantidad').val(),                     csrfmiddlewaretoken: '{{ csrf_token }}',                 },                 sucess:function(){                     alert("ok");                 }             })     });  </script> 

this error: post http://127.0.0.1:8000/cobro/agregar_concepto/ 500 (internal server error)

i think maybe missing in view, buy dont know that, cal me?

edit: traceback added

environment:

request method: request url: http://127.0.0.1:8000/cobro/agregar_concepto/

django version: 1.9.7 python version: 2.7.11 installed applications: ('django.contrib.admin', 'django.contrib.auth', 'django.contrib.contenttypes', 'django.contrib.sessions', 'django.contrib.messages', 'django.contrib.staticfiles', 'entrada', 'cobro', 'catalogo', 'selectize', 'smart_selects') installed middleware: ('django.contrib.sessions.middleware.sessionmiddleware', 'django.middleware.common.commonmiddleware', 'django.middleware.csrf.csrfviewmiddleware', 'django.contrib.auth.middleware.authenticationmiddleware', 'django.contrib.auth.middleware.sessionauthenticationmiddleware', 'django.contrib.messages.middleware.messagemiddleware', 'django.middleware.clickjacking.xframeoptionsmiddleware')

traceback:

file "c:\python27\lib\site-packages\django\core\handlers\base.py" in get_response 158. % (callback.module, view_name))

exception type: valueerror @ /cobro/agregar_concepto/ exception value: view cobro.views.addconcept_product didn't return httpresponse object. returned none instead.

you view not complete: exception states: view cobro.views.addconcept_product didn't return proper httpresponse object.

return httpresponseredirect('/thanks/')