django get_or_create 返回错误：“tuple”对象没有属性

我是 django 新手，我正在尝试使用 get_or_create 模型函数，但即使我的模型中有该属性，我也会收到错误

AttributeError at /professor/adicionar-compromisso
'tuple' object has no attribute 'dias'
Request Method: POST
Request URL:    http://localhost:8000/professor/adicionar-compromisso
Django Version: 1.4.1
Exception Type: AttributeError
Exception Value:    
'tuple' object has no attribute 'dias'
Exception Location: c:\htdocs\rpv\GerenDisponibilidade\professor\models.py in inserirCompromisso, line 63
Python Executable:  C:\Python27\python.exe
Python Version: 2.7.3
Python Path:    
['c:\\htdocs\\rpv\\GerenDisponibilidade',
 'C:\\Python27\\lib\\site-packages\\distribute-0.6.27-py2.7.egg',
 'C:\\Python27\\lib\\site-packages\\pip-1.1-py2.7.egg',
 'C:\\Python27\\lib\\site-packages\\sphinx-1.1.3-py2.7.egg',
 'C:\\Python27\\lib\\site-packages\\docutils-0.9.1-py2.7.egg',
 'C:\\Python27\\lib\\site-packages\\jinja2-2.6-py2.7.egg',
 'C:\\Python27\\lib\\site-packages\\pygments-1.5-py2.7.egg',
 'C:\\Windows\\system32\\python27.zip',
 'C:\\Python27\\DLLs',
 'C:\\Python27\\lib',
 'C:\\Python27\\lib\\plat-win',
 'C:\\Python27\\lib\\lib-tk',
 'C:\\Python27',
 'C:\\Python27\\lib\\site-packages',
 'C:\\Python27\\lib\\site-packages\\setuptools-0.6c11-py2.7.egg-info']
Server time:    Seg, 3 Set 2012 17:57:17 -0300

Model

class DiaSemana(models.Model):    
DIAS_CHOICES = (
                ("Seg", "Segunda-Feira"),
                ("Ter", "Terça-Feira"),
                ("Qua", "Quarta-Feira"),
                ("Qui", "Quinta-Feira"),
                ("Sex", "Sexta-Feira"),
                ("Sab", "Sábado"),
                ("Dom", "Domingo"),
                )           
dias = models.CharField(max_length=20, choices=DIAS_CHOICES) 

在这里我尝试搜索以检查是否存在现有值，否则创建新值并保存

for diaSemana in diaSemanas:
        d = DiaSemana.objects.get_or_create(dias=diaSemana)
        d.dias = diaSemana;
        d.save() 
        c.save()
        c.diaSemana.add(d);

怎么了？

get_or_create https://docs.djangoproject.com/en/dev/ref/models/querysets/#get-or-create不只是返回对象：

返回一个元组(object, created)，其中 object 是检索或创建的对象，created 是一个布尔值，指定是否创建了新对象。

在你的情况下d已分配此元组而不是您期望的对象，因此您会收到属性错误。您可以通过将代码更改为以下内容来修复代码：

d, created = DiaSemana.objects.get_or_create(dias=diaSemana)

以下两行对我来说似乎没有必要。这get_or_create上面的调用确保d.dias=diaSemana，所以不需要再次赋值。可能不需要打电话save either.

d.dias = diaSemana;
d.save()