can't import name 'CommentForm'

[arsenal1447]

ImportError at /post/5/comment/
cannot import name 'CommentForm'
Request Method: GET
Request URL:    http://localhost:8000/post/5/comment/
Django Version: 1.8
Exception Type: ImportError
Exception Value:    
cannot import name 'CommentForm'
Exception Location: E:\pywork\djangogirls\blog\views.py in <module>, line 6
Python Executable:  E:\Python35\python.exe
Python Version: 3.5.0
Python Path:    
['E:\\pywork\\djangogirls',
 'E:\\Python35\\lib\\site-packages\\django_debug_toolbar-1.4-py3.5.egg',
 'E:\\Python35\\lib\\site-packages\\sqlparse-0.1.19-py3.5.egg',
 'E:\\Python35\\python35.zip',
 'E:\\Python35\\DLLs',
 'E:\\Python35\\lib',
 'E:\\Python35',
 'E:\\Python35\\lib\\site-packages']
Server time:    Thu, 16 Jun 2016 17:02:11 +0800

when I study this course https://github.com/DjangoGirls/tutorial-extensions/blob/master/homework_create_more_models/README.md . run this url

http://localhost:8000/post/5/comment/

I get this error.

can u help me to fix this?Thank u.

[arsenal1447]

http://imgchr.com/images/6392QL_J8S_5DQKCCF4BV.png

here is the error pic

[arsenal1447]

This is my /blog/view.py file

from django.shortcuts import render
#from django.utils import timezone
from datetime import datetime
from .models import Post
from .forms import PostForm, CommentForm
from django.shortcuts import render,get_object_or_404
from django.shortcuts import redirect
from django.contrib.auth.decorators import login_required

def post_list(request):
    posts = Post.objects.filter(published_date__lte=datetime.now()).order_by('published_date')
    return render(request,'blog/post_list.html',{'posts':posts})

def post_detail(request,pk):
    post = get_object_or_404(Post,pk=pk)
    return render(request,'blog/post_detail.html',{'post':post})

@login_required
def post_new(request):
    if request.method == "POST":
        form = PostForm(request.POST)
        if form.is_valid():
            post = form.save(commit=False)
            post.author = request.user
            # post.published_date = datetime.now()
            post.save()
            return redirect('blog.views.post_detail', pk=post.pk)
    else:
        form = PostForm()
    return render(request, 'blog/post_edit.html', {'form': form})

@login_required
def post_edit(request, pk):
    post = get_object_or_404(Post, pk=pk)
    if request.method == "POST":
        form = PostForm(request.POST, instance=post)
        if form.is_valid():
            post = form.save(commit=False)
            post.author = request.user
            post.published_date = datetime.now()
            post.save()
            return redirect('blog.views.post_detail', pk=post.pk)
    else:
        form = PostForm(instance=post)
    return render(request, 'blog/post_edit.html', {'form': form})

@login_required
def post_draft_list(request):
    posts = Post.objects.filter(published_date__isnull=True).order_by('created_date')
    return render(request,'blog/post_draft_list.html',{'posts':posts})

@login_required
def post_publish(request,pk):
    post = get_object_or_404(Post,pk=pk)
    post.publish()
    return redirect('blog.views.post_detail',pk=pk)

@login_required
def post_remove(request,pk):
    post = get_object_or_404(Post,pk=pk)
    post.delete()
    return redirect('blog.views.post_list')

def add_comment_to_post(request,pk):
    post = get_object_or_404(Post,pk=pk)
    if request.method == "POST":
        form = CommentForm(request.POST)
        if form.is_valid():
            comment = form.save(commit=False)
            comment.post = post
            comment.save()
            return redirect('blog.views.post_detail',pk=post.pk)
    else:
        form = CommentForm()
    return render(request,'blog/add_comment_to_post.html',{'form' : form})