def login(request):
    # blahblah
    username = request.POST.get('username', '')
    password = request.POST.get('password', '')
    user = auth.authenticate(username=username, password=password)
    if user is not None and user.is_active:
        auth.login(request, user)
    # blahblah 我后面是返回jason然后让前端刷新页面，代码就不贴了。。

class Activity(models.Model):
    user_list = models.ManyToManyField(User, related_name='users', null=True, blank=True)

User.objects.all().values('name','age')

 def _clean_fields(self):
        for name, field in self.fields.items():
            # value_from_datadict() gets the data from the data dictionaries.
            # Each widget type knows how to retrieve its own data, because some
            # widgets split data over several HTML fields.
            if field.disabled:
                value = self.initial.get(name, field.initial)
            else:
                value = field.widget.value_from_datadict(self.data, self.files, self.add_prefix(name))
            try:
                if isinstance(field, FileField):
                    initial = self.initial.get(name, field.initial)
                    value = field.clean(value, initial)
                else:
                    value = field.clean(value)
                self.cleaned_data[name] = value
                if hasattr(self, 'clean_%s' % name):
                    value = getattr(self, 'clean_%s' % name)()
                    self.cleaned_data[name] = value
            except ValidationError as e:
                self.add_error(name, e)

t = open(file_time +"book_info.txt", 'r')
for i in t.read():
     #blahblah

 subject_category_raws = Discovery.objects.values(
        'subject',
        'subject__name',
        'category',
        'category__name').order_by(
        'subject',
        'category').annotate(ccount=Count('category'))

#blabla
from django.shortcuts import render_to_response, RequestContext

def listt(request):
    if request.method=='POST':
        return HttpResponse('hello world')
    form= mybook()
    return render_to_response('2.html',{'form':form},context_instance=RequestContext(request),)

def is_valid(self):
    """
    Returns True if the form has no errors. Otherwise, False. If errors are
    being ignored, returns False.
    """
    return self.is_bound and not self.errors