Update app.py

app.py

@@ -13,13 +13,13 @@ class ArticleRequesteng(BaseModel):
     article_title: str
     main_keyword: str
     target_tone: str
-    optional_text: str
+    optional_text: str = None
 # Define the request model
 class ArticleRequest(BaseModel):
     titre_article: str
     mot_cle_principal: str
     ton_cible: str
-    optional_text : str
+    optional_text : str = None
 
 # Define the response model
 class ArticleResponse(BaseModel):