我创建了www.example.com模块，其中包含test.py module, filled with

from django.test import TestCase
from django.test.client import Client
from django.contrib.auth.models import User
from django.contrib.sites.models import Site

from forum.models import *

class SimpleTest(TestCase):

    def setUp(self):
        u = User.objects.create_user("ak", "ak@abc.org", "pwd")
        Forum.objects.create(title="forum")
        Site.objects.create(domain="test.org", name="test.org")

    def content_test(self, url, values):
        """Get content of url and test that each of items in `values` list is present."""
        r = self.c.get(url)
        self.assertEquals(r.status_code, 200)
        for v in values:
            self.assertTrue(v in r.content)

    def test(self):
        self.c = Client()
        self.c.login(username="ak", password="pwd")

        self.content_test("/forum/", ['<a href="/forum/forum/1/">forum</a>'])
        ....

并将其与我的应用程序一起放在文件夹中。当我通过

python manage.py test forum

创建测试数据库后，我得到答案"在0.000s内运行0次测试"
我做错了什么？
P.S.以下是我的项目层次结构：

MyProj:
    forum (it's my app):
        manage.py
        models.py
        views.py
        tests.py
        ...

我将www.example.com重命名为tests.py。Eclipse发现此模块包含测试，但答案仍然是"在0.000s内运行0个测试"test.py to tests.py. Eclipse got that this module is with tests, but answer is still "Ran 0 tests in 0.000s"