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Django app Polls: AttributeError: "Choice" object has no "question_text" attribute

I was doing a tutorial on the Django site when I got this error. I am using OS X 10.10.

>>> q.choice_set.create(choice_text='Not much', votes=0)
Traceback (most recent call last):
  File "<console>", line 1, in <module>
  File "/Library/Python/2.7/site-packages/Django-1.7.8-py2.7.egg/django/db/models/base.py", line 458, in __repr__
    u = six.text_type(self)
  File "/Users/anushrutgupta/Documents/IMG/Django/mysite/polls/models.py", line 22, in __str__
    return self.choice_text
AttributeError: 'Choice' object has no attribute 'question_text'
>>>

My .py models:

import datetime

from django.db import models
from django.utils import timezone

class Question(models.Model):
    question_text = models.CharField(max_length=200)
    pub_date = models.DateTimeField('date published')

    def __str__(self):  
        return self.question_text

    def was_published_recently(self):
        return self.pub_date >= timezone.now() -datetime.timedelta(days=1)

class Choice(models.Model):
    question = models.ForeignKey(Question)
    choice_text = models.CharField(max_length=200)
    votes = models.IntegerField(default=0)

    def __str__(self):   
        return self.choice_text

Is there something wrong with the models?

+4


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5 answers


Looks like a typo in your code on line 22 of models.py

, you have return self.question_text

, but it should be return self.choice_text

.

EDIT : I see you are using Python 2.7, with Python 2 you need to use __unicode__

, not __str__

.



__str__

or __unicode__

?

In Python 3, just use __str__()

.

In Python 2, you must define methods __unicode__()

that return unicode values. Django models have a __str__()

default method that calls __unicode__()

and converts the result to UTF-8. This means it unicode(p)

will return a Unicode string, but it str(p)

will return a byte string with characters encoded as UTF-8. Python does the opposite: an object has a method __unicode__

that calls __str__

and interprets the result as an ASCII byte string. This difference can be confusing.

If this is all gibberish to you, just use Python 3.

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So when defining q

, please use .get()

if you haven't already.
You can read the difference between .filter()

and .get()

in the official documentation.
As far as I remember, .filter()

does not contain an object that you can manipulate using its attributes.



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I found a solution to this problem, I was making the same mistake too when you define the variable q,

q = Question.objects.get(pk=1) #it should be like this
q.choice_set.all() #this will show an empty list (only if it empty)
q.choice_set.create(choice_text="sheela ki jawani", votes=0) #and so on

I was doing the first step of incorrectly defining q instead of .get (pk = 1), I used

q = Question.objects.all() #this is wrong
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I am doing the same exercise and based on your code that I was able to complete. (show the question: what?). I have to say that the step-by-step instructions in the tutorial are rather confusing.

My code has two extra lines:

 from __future__ import unicode_literals # future between underscores, 2 on each side

and

from django.utils.encoding import python_2_unicode_compatible
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So, the two tables are linked with the foreign key "question"

For the "Question" table to be related to the "Variants" table, you must add a Foreign_eyField parameter named "related_name"

So, to map questions with 1 or n choices, you can use the related name

The code will look like this:

class Choices(models.Model):
    question = models.ForeignKey(Question, on_delete=models.CASCADE, 
    related_name="choice_set")
    choice_text = models.CharField(max_length=200)
    votes = models.IntegerField(default=0)
0


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