Erreur STRIPE_API_KEY lors du lancement du serveur avec une clé API de test

(env_cha) PS D:\Mes Projets\Chaïma> py manage.py runserver
Invalid line: STRIPE_API_KEY = "nepasmontrer"
Invalid line: STRIPE_API_KEY = "nepasmontrer"
Invalid line: STRIPE_API_KEY = "nepasmontrer"
Traceback (most recent call last):
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\environ\environ.py", line 409, in get_value
    value = self.ENVIRON[var_name]
            ~~~~~~~~~~~~^^^^^^^^^^
  File "<frozen os="">", line 716, in __getitem__
KeyError: 'STRIPE_API_KEY'

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

Traceback (most recent call last):
  File "D:\Mes Projets\Chaïma\manage.py", line 22, in <module>
    main()
    ~~~~^^
  File "D:\Mes Projets\Chaïma\manage.py", line 18, in main
    execute_from_command_line(sys.argv)
    ~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\core\management\__init__.py", line 442, in execute_from_command_line
    utility.execute()
    ~~~~~~~~~~~~~~~^^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\core\management\__init__.py", line 436, in execute
    self.fetch_command(subcommand).run_from_argv(self.argv)
    ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\core\management\base.py", line 416, in run_from_argv
    self.execute(*args, **cmd_options)
    ~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\core\management\commands\runserver.py", line 69, in execute
    super().execute(*args, **options)
    ~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\core\management\base.py", line 460, in execute
    output = self.handle(*args, **options)
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\core\management\commands\runserver.py", line 80, in handle
    if not settings.DEBUG and not settings.ALLOWED_HOSTS:
           ^^^^^^^^^^^^^^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\conf\__init__.py", line 81, in __getattr__
    self._setup(name)
    ~~~~~~~~~~~^^^^^^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\conf\__init__.py", line 68, in _setup
    self._wrapped = Settings(settings_module)
                    ~~~~~~~~^^^^^^^^^^^^^^^^^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\django\conf\__init__.py", line 166, in __init__
    mod = importlib.import_module(self.SETTINGS_MODULE)
  File "C:\Users\ulric\AppData\Local\Programs\Python\Python313\Lib\importlib\__init__.py", line 88, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
           ~~~~~~~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
  File "<frozen importlib._bootstrap="">", line 1387, in _gcd_import
  File "<frozen importlib._bootstrap="">", line 1360, in _find_and_load
  File "<frozen importlib._bootstrap="">", line 1331, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap="">", line 935, in _load_unlocked
  File "<frozen importlib._bootstrap_external="">", line 1022, in exec_module
  File "<frozen importlib._bootstrap="">", line 488, in _call_with_frames_removed
  File "D:\Mes Projets\Chaïma\chacha\settings.py", line 139, in <module>
    STRIPE_API_KEY = env("STRIPE_API_KEY")
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\environ\environ.py", line 207, in __call__
    return self.get_value(
           ~~~~~~~~~~~~~~^
        var,
        ^^^^
    ...<2 lines>...
        parse_default=parse_default
        ^^^^^^^^^^^^^^^^^^^^^^^^^^^
    )
    ^
  File "D:\Mes Projets\Chaïma\env_cha\Lib\site-packages\environ\environ.py", line 413, in get_value
    raise ImproperlyConfigured(error_msg) from exc
django.core.exceptions.ImproperlyConfigured: Set the STRIPE_API_KEY environment variable
(env_cha) PS D:\Mes Projets\Chaïma>