python - The view app.views.model didn't return an HttpResponse object -

this views.py file. on way generate xml file, data getting mysql. first time working make changes cant remember did s not working ...

in views.py

def messageheadermodel2(request):     if request.method == "post":             form = messageheaderform(request.post)                     if form.is_valid():                             ddex_party_id = request.post.get('ddex_party_id',none)                             data = serializers.serialize("xml", messageheadermodel2.objects.all())                             open("file.xml", "w") out:                             xml_serializer.serialize(messageheadermodel2.obj    ects.all(), stream=out) 

the error gettin

>exception type:valueerror exception value:the view app.views.messageheadermodel2 didn't return httpresponse object. 

you in fact not returning httpresponse object!

django views must return instance of httpresponse @ end of view:

from django.http import httpresponse  def view(request):     ...     return httpresponse("the page content") 

you can return may other subclasses of httpresponse, see documentation list.

you can use of shortcut functions render page using django templating system, again documentation helpful here, briefly:

from django.shortcuts import render_to_response  def view(request):     ...     return render_to_response('my_template.html',                               my_data_dictionary,                               context_instance=requestcontext(request)) 

a complete example using code above:

def view(request):     if request.method == "post":         form = messageheaderform(request.post)         if form.is_valid():             ddex_party_id = request.post.get('ddex_party_id',none)             data = serializers.serialize("xml", messageheadermodel2.objects.all())             open("file.xml", "w") out:                 out.write(data)             return httpresponse(data)         else:             # return error response?     return httpresponsenotallowed(['post'])