python – 导入错误：没有名为transaction的模块

/usr/local/lib/python2.7/dist-packages/django/contrib/admin/models.py:28: RemovedInDjango19Warning: Model class django.contrib.admin.models.LogEntry doesn't declare an explicit app_label and either isn't in an application in INSTALLED_APPS or else was imported before its application was loaded. This will no longer be supported in Django 1.9.
  class LogEntry(models.Model):
/usr/local/lib/python2.7/dist-packages/django/contrib/admin/models.py:28: RemovedInDjango19Warning: Model class django.contrib.admin.models.LogEntry doesn't declare an explicit app_label and either isn't in an application in INSTALLED_APPS or else was imported before its application was loaded. This will no longer be supported in Django 1.9.
  class LogEntry(models.Model):
Performing system checks...
System check identified no issues (0 silenced).
You have unapplied migrations; your app may not work properly until they are applied.
Run 'python manage.py migrate' to apply them.
octubre 13,2015 - 08:57:36
Django version 1.8.4,using settings 'spid.settings'
Starting development server at http://127.0.0.1:8000/
Quit the server with CONTROL-C.

在简单的视图显示一切正常,但当我尝试在浏览器中打开网址时,我在浏览器中收到此错误：

A server error occurred. Please contact the administrator.

和控制台中的此错误：

Traceback (most recent call last):
  File "/usr/lib/python2.7/wsgiref/handlers.py",line 85,in run
    self.result = application(self.environ,self.start_response)
  File "/usr/local/lib/python2.7/dist-packages/django/contrib/staticfiles/handlers.py",line 63,in __call__
    return self.application(environ,start_response)
  File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/wsgi.py",line 170,in __call__
    self.load_middleware()
  File "/usr/local/lib/python2.7/dist-packages/django/core/handlers/base.py",line 50,in load_middleware
    mw_class = import_string(middleware_path)
  File "/usr/local/lib/python2.7/dist-packages/django/utils/module_loading.py",line 26,in import_string
    module = import_module(module_path)
  File "/usr/lib/python2.7/importlib/__init__.py",line 37,in import_module
    __import__(name)
ImportError: No module named transaction
[13/Oct/2015 09:03:51] "GET /spid/ HTTP/1.1" 500 59
Traceback (most recent call last):
  File "/usr/lib/python2.7/wsgiref/handlers.py",in import_module
    __import__(name)
ImportError: No module named transaction
[13/Oct/2015 09:03:51] "GET /favicon.ico HTTP/1.1" 500 59