Djangoでurls.pyでImportErrorがでる

Question

前提・実現したいこと

Helloworldと表示させるプログラムをつくりたい

発生している問題・エラーメッセージ

projectのファイル内に移動して　python manage.py runserver
を実行すると次のエラーがでる

Unhandled exception in thread started by <function wrapper at 0x7f14e9951d50>
Traceback (most recent call last):
  File "/usr/lib/python2.7/dist-packages/django/utils/autoreload.py", line 228, in wrapper
    fn(*args, **kwargs)
  File "/usr/lib/python2.7/dist-packages/django/core/management/commands/runserver.py", line 124, in inner_run
    self.check(display_num_errors=True)
  File "/usr/lib/python2.7/dist-packages/django/core/management/base.py", line 359, in check
    include_deployment_checks=include_deployment_checks,
  File "/usr/lib/python2.7/dist-packages/django/core/management/base.py", line 346, in _run_checks
    return checks.run_checks(**kwargs)
  File "/usr/lib/python2.7/dist-packages/django/core/checks/registry.py", line 81, in run_checks
    new_errors = check(app_configs=app_configs)
  File "/usr/lib/python2.7/dist-packages/django/core/checks/urls.py", line 16, in check_url_config
    return check_resolver(resolver)
  File "/usr/lib/python2.7/dist-packages/django/core/checks/urls.py", line 26, in check_resolver
    return check_method()
  File "/usr/lib/python2.7/dist-packages/django/urls/resolvers.py", line 256, in check
    for pattern in self.url_patterns:
  File "/usr/lib/python2.7/dist-packages/django/utils/functional.py", line 35, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/usr/lib/python2.7/dist-packages/django/urls/resolvers.py", line 407, in url_patterns
    patterns = getattr(self.urlconf_module, "urlpatterns", self.urlconf_module)
  File "/usr/lib/python2.7/dist-packages/django/utils/functional.py", line 35, in __get__
    res = instance.__dict__[self.name] = self.func(instance)
  File "/usr/lib/python2.7/dist-packages/django/urls/resolvers.py", line 400, in urlconf_module
    return import_module(self.urlconf_name)
  File "/usr/lib/python2.7/importlib/__init__.py", line 37, in import_module
    __import__(name)
  File "/mnt/c/Users/user/Documents/Python Scripts/Django/helloworld/helloworldproject/helloworldproject/urls.py", line 18, in <module>
    from views import helloworldfunction
ImportError: cannot import name helloworldfunction

ソースコード

1.urls.py
"""helloworldproject URL Configuration

The `urlpatterns` list routes URLs to views. For more information please see:
    https://docs.djangoproject.com/en/1.11/topics/http/urls/
Examples:
Function views
    1. Add an import:  from my_app import views
    2. Add a URL to urlpatterns:  url(r'^$', views.home, name='home')
Class-based views
    1. Add an import:  from other_app.views import Home
    2. Add a URL to urlpatterns:  url(r'^$', Home.as_view(), name='home')
Including another URLconf
    1. Import the include() function: from django.conf.urls import url, include
    2. Add a URL to urlpatterns:  url(r'^blog/', include('blog.urls'))
"""
from django.conf.urls import url
from django.contrib import admin
from views import helloworldfunction

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^helloworld/', helloworldfunction)
]

##############

2.viwes.py
from django.http import HttpResponse

def helloworldfunction(request):
    returnobject = HttpResponse("hello world")
    return returnobject

試したこと

スペルミスがないかどうか確認をした

補足情報（FW/ツールのバージョンなど）

VSCodeで実行している

Answer 1

修正したファイルを保存せずに実行していたのでエラーがでていました。
保存して再度実行したら、成功しました

Answer 2

それは、プロジェクト下のurls.pyでviewsを呼んでるからです。
例えばappというアプリを作っているとすると、

└─helloworldproject
    │  db.sqlite3
    │  manage.py
    │
    ├─helloworldproject
    │  │  asgi.py
    │  │  settings.py
    │  │  urls.py
    │  │  wsgi.py
    │
    └─app
        │  admin.py
        │  apps.py
        │  models.py
        │  tests.py
        │  urls.py   # ←―ここにも作る
        │  views.py
```そして、helloworldproject/helloworldproject/urls.pyを
```Python
from django.urls import include  # 新規
from django.conf.urls import url
from django.contrib import admin

urlpatterns = [
    url(r'^admin/', admin.site.urls),
    url(r'^helloworld/', include("app/urls"))  # 新規
]
```として、新しく作ったhelloworldproject/app/urls.pyを
```Python
from django.urls import path
from views import helloworldfunction
urlpatterns = [
    path('', helloworldfunction),
]
```とします。