코드스니펫 그대로 넣은겁니다.

왜 오류가 나는거죠?

작성한 코드 및 에러 메세지

C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\Scripts\python.exe C:/Users/hongkiwoo/Desktop/sparta/projects/mars/app.py

 * Serving Flask app 'app'

 * Debug mode: on

WARNING: This is a development server. Do not use it in a production deployment. Use a production WSGI server instead.

 * Running on all addresses (0.0.0.0)

 * Running on http://127.0.0.1:5000

 * Running on http://192.168.0.156:5000

Press CTRL+C to quit

 * Restarting with stat

 * Debugger is active!

 * Debugger PIN: 372-502-108

127.0.0.1 - - [24/Nov/2022 11:39:19] "GET / HTTP/1.1" 500 -

Traceback (most recent call last):

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\app.py", line 2548, in __call__

  return self.wsgi_app(environ, start_response)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\app.py", line 2528, in wsgi_app

  response = self.handle_exception(e)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\app.py", line 2525, in wsgi_app

  response = self.full_dispatch_request()

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\app.py", line 1822, in full_dispatch_request

  rv = self.handle_user_exception(e)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\app.py", line 1820, in full_dispatch_request

  rv = self.dispatch_request()

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\app.py", line 1796, in dispatch_request

  return self.ensure_sync(self.view_functions[rule.endpoint])(**view_args)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\app.py", line 6, in home

  return render_template('index.html')

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\templating.py", line 146, in render_template

  template = app.jinja_env.get_or_select_template(template_name_or_list)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\jinja2\environment.py", line 1081, in get_or_select_template

  return self.get_template(template_name_or_list, parent, globals)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\jinja2\environment.py", line 1010, in get_template

  return self._load_template(name, globals)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\jinja2\environment.py", line 969, in _load_template

  template = self.loader.load(self, name, self.make_globals(globals))

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\jinja2\loaders.py", line 126, in load

  source, filename, uptodate = self.get_source(environment, name)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\templating.py", line 62, in get_source

  return self._get_source_fast(environment, template)

 File "C:\Users\hongkiwoo\Desktop\sparta\projects\mars\venv\lib\site-packages\flask\templating.py", line 98, in _get_source_fast

  raise TemplateNotFound(template)

jinja2.exceptions.TemplateNotFound: index.html

127.0.0.1 - - [24/Nov/2022 11:39:22] "GET /?__debugger__=yes&cmd=resource&f=style.css HTTP/1.1" 304 -

127.0.0.1 - - [24/Nov/2022 11:39:22] "GET /?__debugger__=yes&cmd=resource&f=debugger.js HTTP/1.1" 304 -

127.0.0.1 - - [24/Nov/2022 11:39:23] "GET /?__debugger__=yes&cmd=resource&f=console.png HTTP/1.1" 304 -

127.0.0.1 - - [24/Nov/2022 11:39:23] "GET /?__debugger__=yes&cmd=resource&f=console.png HTTP/1.1" 304 -