解决Django中set_cookie()不能存储中文字符串问题

def get(self,request):
    if 'username' in request.COOKIES:
        username=request.COOKIES.get('username')
    else:
        username=''
    trans_uname=json.loads(username)
    return render_to_response('login.html',{'username':trans_uname})
def post(self,request):
    username=request.POST.get('username')
    pwd=request.POST.get('pwd')
    record=request.POST.get('checkbox')
    #数据的校验
    if not all([username,pwd]):
        return render_to_response('login.html',{'info':'数据填入不完整'})

    #验证用户的身份，验证用户名和密码是否存在数据库中
    user=authenticate(username=username,password=pwd)

    if user is not None:
        if user.is_active:
            login(request, user)

            response = redirect('/')
            if record=='on':
                trans_uname=json.dumps(username)
                response.set_cookie('username',trans_uname)
            return response