vsc로 파일을 열었는데 Internal Server Error가 나옵니다.
터미널에서는 이렇게 나옵니다. 도와주시면 감사하겠습니다.
PS C:\Users\지성\Desktop\드림핵> & 'C:\Users\지성\AppData\Local\Microsoft\WindowsApps\python3.9.exe' 'c:\Users\지성.vscode\extensions\ms-python.python-2022.0.1786462952\pythonFiles\lib\python\debugpy\launcher' '12605' '--' '-m' 'flask' 'run' '--no-debugger'

• Serving Flask app 'app.py' (lazy loading)
• Environment: development
• Debug mode: on
  C:\Users\지성\Desktop\드림핵\app.py:40: Warning: Silently ignoring app.run() because the application is run from the flask command line executable. Consider putting app.run() behind an if name == "main" guard to silence this warning.
  app.run(host='0.0.0.0', port=8000)
• Restarting with stat
• Running on http://127.0.0.1:5000/ (Press CTRL+C to quit)
  127.0.0.1 - - [05/Feb/2022 17:24:47] "GET / HTTP/1.1" 500 -
  Error on request:
  Traceback (most recent call last):
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\werkzeug\serving.py", line 319, in run_wsgi
  execute(self.server.app)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\werkzeug\serving.py", line 308, in execute
  application_iter = app(environ, start_response)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\app.py", line 2091, in call
  return self.wsgi_app(environ, start_response)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\app.py", line 2076, in wsgi_app
  response = self.handle_exception(e)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\app.py", line 2073, in wsgi_app
  response = self.full_dispatch_request()
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\app.py", line 1518, in full_dispatch_request
  rv = self.handle_user_exception(e)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\app.py", line 1516, in full_dispatch_request
  rv = self.dispatch_request()
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\app.py", line 1502, in dispatch_request
  return self.ensure_sync(self.view_functions[rule.endpoint])(**req.view_args)
  File "C:\Users\지성\Desktop\드림핵\app.py", line 20, in index
  return render_template('index.html', text=f'Hello {username}, {"flag is " + FLAG if username == "admin" else "you are not admin"}')
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\templating.py", line 148, in render_template
  ctx.app.jinja_env.get_or_select_template(template_name_or_list),
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\jinja2\environment.py", line 1068, in get_or_select_template
  return self.get_template(template_name_or_list, parent, globals)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\jinja2\environment.py", line 997, in get_template
  return self._load_template(name, globals)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\jinja2\environment.py", line 958, in _load_template
  template = self.loader.load(self, name, self.make_globals(globals))
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\jinja2\loaders.py", line 125, in load
  source, filename, uptodate = self.get_source(environment, name)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\templating.py", line 59, in get_source
  return self._get_source_fast(environment, template)
  File "C:\Users\지성\AppData\Local\Packages\PythonSoftwareFoundation.Python.3.9_qbz5n2kfra8p0\LocalCache\local-packages\Python39\site-packages\flask\templating.py", line 95, in _get_source_fast
  raise TemplateNotFound(template)
  jinja2.exceptions.TemplateNotFound: index.html