What does join do in django's views.py?

output=','.join([q.question_text for qin latest_question_list])

 from django.http import HttpResponse

from.models import Question

# q.question_text has only one object: <Question: What's new?>

def index(request):
    latest_question_list =Question.objects.order_by('-pub_date') [:5]
    output=','.join([q.question_text for qin latest_question_list])
    return HttpResponse (output)

# Leave the rest of the views (detail, results, voice) unchanged

import datetime

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

# Create your models here.
class Question (models.Model):
    question_text=models.CharField(max_length=200)
    pub_date=models.DateTimeField('date published2')
    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, on_delete=models.CASCADE)
    choice_text=models.CharField(max_length=200)
    votes=models.IntegerField(default=0)
    def__str__(self):
        return self.choice_text