Python Django 调试

    	>>> class Person(models.Model):...     first_name = models.CharField(max_length = 50)...     last_name = models.CharField(max_length = 50)...     def __unicode__(self):...         return u'%s %s' %(self.first_name ,self.last_name)... Traceback (most recent call last):File "
    
     ", line 1, in 
     
      File "/usr/lib/python2.7/site-packages/django/db/models/base.py", line 117, in __new__	kwargs = {"app_label": package_components[app_label_index]}IndexError: list index out of range
     
    

模型的定义必须在应用程序中-你看到那里它试图采取 name model_module 错误-这应该有一些像为 project\appname\models.py-project.appname.models，并获得该应用程序的名称，appname 来。在交互式的控制台中，该模块 name 是 'main',所以它会失败。

为了解决这个问题，你需要在元类 自己指定的 app_label，

    	>>> from django.db import models>>> class Poll(models.Model):...     question = models.CharField(max_length=200)...     pub_date = models.DateTimeField('date published')...     class Meta:...         app_label = 'test'

解释为什么你可以做到，看看在回溯(traceback)的时候，/usr/lib/python2.7/site-packages/django/db/models/base.py 中提到该文件：

if getattr(meta, 'app_label', None) is None:    # Figure out the app_label by looking one level up.    # For 'django.contrib.sites.models', this would be 'sites'.    model_module = sys.modules[new_class.__module__]    kwargs = {"app_label": model_module.__name__.split('.')[-2]}else:    kwargs = {}

元类在哪里定义呢？，见上方在该文件中。