traceback

ValueError at /post/new/
Cannot assign "<SimpleLazyObject: <django.contrib.auth.models.AnonymousUser object at 0x03D807F0>>": "Post.author" must be a "User" instance.
Request Method:	POST
Request URL:	http://localhost:8000/post/new/
Django Version:	1.9.8
Exception Type:	ValueError
Exception Value:
Cannot assign "<SimpleLazyObject: <django.contrib.auth.models.AnonymousUser object at 0x03D807F0>>": "Post.author" must be a "User" instance.
Exception Location:	C:\Users\jalal\myvenv\lib\site-packages\django\db\models\fields\related_descriptors.py in __set__, line 207
Python Executable:	C:\Users\jalal\myvenv\Scripts\python.exe
Python Version:	3.4.2
Python Path:
['C:\\Users\\jalal\\monadjango',
 'C:\\WINDOWS\\system32\\python34.zip',
 'C:\\Python34\\DLLs',
 'C:\\Python34\\lib',
 'C:\\Python34',
 'C:\\Users\\jalal\\myvenv',
 'C:\\Users\\jalal\\myvenv\\lib\\site-packages']
Server time:	Mon, 18 Jul 2016 19:35:15 -0500
Traceback Switch to copy-and-paste view

C:\Users\jalal\myvenv\lib\site-packages\django\core\handlers\base.py in get_response
                    response = self.process_exception_by_middleware(e, request) ...
▶ Local vars
C:\Users\jalal\myvenv\lib\site-packages\django\core\handlers\base.py in get_response
                    response = wrapped_callback(request, *callback_args, **callback_kwargs) ...
▶ Local vars
C:\Users\jalal\monadjango\blog\views.py in post_new
            post.author = request.user ...
▶ Local vars
C:\Users\jalal\myvenv\lib\site-packages\django\db\models\fields\related_descriptors.py in __set__
                    self.field.remote_field.model._meta.object_name, ...
▶ Local vars