def __str__ This should be the class method of the model Question. This method determines the return when you query. You define return self.question_text, so when you query the object, it will return the question_text attribute of the object, but your writing The format is wrong. If this method is defined outside the class, it becomes a single function and has nothing to do with the class. When you query, a Question object will be returned by default.

Thanks to tianren124 for the answer, the problem has been solved.
First you need to modify models.py:
models.py

# Create your models here. class Question(models.Model): def __str__(self): return self.question_text question_text = models.CharField(max_length=200) pub_date = models.DateTimeField('date published') class Chioce(models.Model): def __str__(self): return self.choice_text question = models.ForeignKey(Question, on_delete=models.CASCADE) choice_text = models.CharField(max_length=200) votes = models.IntegerField(default=0) # 每个模型是django.db.models.Model类的子类 #def was_published_recently(self): #return self.pub_date >= timezone.now() - datetime.timedelta(days=1)

After changing the model.py code above, save it, open cmd, and re-enter it

C:\Users\Administrator\AppData\Local\Programs\Python\Python35\myproject>python m anage.py runserver

Enter simultaneously

C:\Users\Administrator\AppData\Local\Programs\Python\Python35\myproject>python m anage.py shell Python 3.5.2 (v3.5.2:4def2a2901a5, Jun 25 2016, 22:18:55) [MSC v.1900 64 bit (AM D64)] on win32 Type "help", "copyright", "credits" or "license" for more information. (InteractiveConsole) >>> import django >>> django.setup() >>> from polls.models import Question, Chioce >>> Question.objects.all() [, , ] >>>

You can see that, unlike the results in the previous question, when Question.objects.all() is entered, the running result is the value after I change q.question_tex "What's up?
Solution:
1. Modify models.py

def __str__(self): return self.question_text

should be placed in

question_text = models.CharField(max_length=200) pub_date = models.DateTimeField('date published')

def __str__(self): return self.choice_text

Also put

question = models.ForeignKey(Question, on_delete=models.CASCADE) choice_text = models.CharField(max_length=200) votes = models.IntegerField(default=0)

In front of me, I don’t quite understand why.
2. Pay attention to the indentation:

The expression may not be very clear, please correct me