Code in Tutorial does not work because of a ','

[Roger Rüttimann]

Page: ​https://docs.djangoproject.com/en/4.1/intro/tutorial01/

Code

from django.urls import path

from . import views

urlpatterns = [
    path('', views.index, name='index'),
]

the ',' at the end of path(...) needs to be removed, otherwise an exception is raised and the code does not work.

it should be:

from django.urls import path

from . import views

urlpatterns = [
    path('', views.index, name='index')
]

I am sorry in case I violite some buge tracking conventions. I actually want to continue with the tutorial, but wanted to raise the issue. Thanks for the otherwise greate tutorial! :)

[Mariusz Felisiak]

urlpatterns is a list and this example is a valid Python code. Trac is not a support channel, so if you're having trouble understanding how Python/Django works, see TicketClosingReasons/UseSupportChannels for ways to get help.

[Roger Rüttimann]

Thanks for the comment @Mariusz Felisiak, but even as the code might be valid python, I still think its a bug, because this happens when I copy paste the code of the tutorial and try to run the development server:

(cvmanager) ➜  cvmanager git:(main) ✗ python manage.py runserver
Watching for file changes with StatReloader
Performing system checks...

Exception in thread django-main-thread:
Traceback (most recent call last):
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/urls/resolvers.py", line 717, in url_patterns
    iter(patterns)
TypeError: 'module' object is not iterable

The above exception was the direct cause of the following exception:

Traceback (most recent call last):
  File "/opt/homebrew/Cellar/python@3.10/3.10.8/Frameworks/Python.framework/Versions/3.10/lib/python3.10/threading.py", line 1016, in _bootstrap_inner
    self.run()
  File "/opt/homebrew/Cellar/python@3.10/3.10.8/Frameworks/Python.framework/Versions/3.10/lib/python3.10/threading.py", line 953, in run
    self._target(*self._args, **self._kwargs)
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/utils/autoreload.py", line 64, in wrapper
    fn(*args, **kwargs)
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/core/management/commands/runserver.py", line 134, in inner_run
    self.check(display_num_errors=True)
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/core/management/base.py", line 475, in check
    all_issues = checks.run_checks(
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/core/checks/registry.py", line 88, in run_checks
    new_errors = check(app_configs=app_configs, databases=databases)
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/core/checks/urls.py", line 14, in check_url_config
    return check_resolver(resolver)
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/core/checks/urls.py", line 24, in check_resolver
    return check_method()
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/urls/resolvers.py", line 495, in check
    messages.extend(check_resolver(pattern))
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/core/checks/urls.py", line 24, in check_resolver
    return check_method()
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/urls/resolvers.py", line 494, in check
    for pattern in self.url_patterns:
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/utils/functional.py", line 57, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/Users/rroger/py_virtualenvs/cvmanager/lib/python3.10/site-packages/django/urls/resolvers.py", line 725, in url_patterns
    raise ImproperlyConfigured(msg.format(name=self.urlconf_name)) from e
django.core.exceptions.ImproperlyConfigured: The included URLconf '<module 'cv.urls' from '/Users/rroger/workspace/cvmanager/cv/urls.py'>' does not appear to have any patterns in it. If you see the 'urlpatterns' variable with valid patterns in the file then the issue is probably caused by a circular import.

and without the ',' it works as expected. I think code in a tutorial should run without raisng exceptions.

[Mariusz Felisiak]

I still think its a bug, because this happens when I copy paste the code of the tutorial and try to run the development server:

Maybe there is a bug but not in the tutorial or Django itself, but in your code. You probably made some typo when copying code from the tutorial. Please use one of support channels.

[Roger Rüttimann]

Actually your right, I tried to reprodcue it, but I can not. Now it's working either way, with or without the comma.
Sorry for the unproductive ticket and thanks for the quick feedback!