django文件上传功能

def ci_test(request):
    try:
        if request.POST.has_key("send"):
            xml_string=""
            final_xml = ""
            file_obj = request.FILES.get('file', None)
            for keys in request.POST:
                if request.POST[keys]:
                    print keys,request.POST[keys]
                    xml_string = "<%s>%s</%s>n%s" % (keys,request.POST[keys],keys,xml_string)
            final_xml = "<root>n%s</root>" % xml_string
            dirname = os.path.dirname(os.path.abspath(__file__))
            parent = os.path.split(dirname)[0]
            if request.POST["source"] == "text" and file_obj:
                if file_obj.name.endswith(".txt"):
                    #print parent
                    filepath = "%s/core/emaillist.txt" % parent
                    #print filepath
                    open(filepath,'w').write(file_obj.read())  #注意这里
                else:
                    raise forms.ValidationError("上传文件类型错误！")
            path = "%s/core/config/%s.xml" % (parent,request.POST['txtDate'])
            open(path,'w').write(final_xml.encode('utf-8'))
        else:
            smtp = request.POST['smtp']
            username = request.POST['username']
            passwd = request.POST['passwd']
            title = request.POST['title']  #邮件标题
            content = request.POST['content']  #邮件内容
            attach = request.POST['useattach']  #是否是附件发送
            ctype = request.POST['c_type']  #邮件格式
            testsend = request.POST['testsend']#测试邮箱
            subtem = u"%s:  %s" % (u"测试",title)
            conn = creat_conn(smtp, username, passwd)
            tem = testsend.split(';')
            if ctype.upper() == "HTML":  
                final_body = creat_htmlbody(content)
                    #测试发送，不用记录日志直接传列表
                final_testmail(subtem,final_body,username,tem,conn,attach)
                print "test send  to %s sucess!" % tem
            else:
                final_testmail(subtem,content,username,tem,conn,"test")
                print "test send  to %s sucess!" % tem
        return render(request,'test.html',{"msg":"请求已经提交，关闭本页面即可"})
    except forms.ValidationError:
        print "in my error"
        return render(request,'test.html',{{"msg":"文件类型错误，请重新操作！"}})
    except Exception:
        return render(request,'test.html',{{"msg":"发生错误，请重新操作！"}})

<form action="ci_test" method="post" onsubmit="return validate_form(this);" enctype="multipart/form-data">
<input type="file" name="file"/>
</form>