diff --git a/docs_src/body/tutorial002.py b/docs_src/body/tutorial002.py
index 7f5183908..5cd86216b 100644
--- a/docs_src/body/tutorial002.py
+++ b/docs_src/body/tutorial002.py
@@ -17,7 +17,7 @@ app = FastAPI()
 @app.post("/items/")
 async def create_item(item: Item):
     item_dict = item.dict()
-    if item.tax:
+    if item.tax is not None:
         price_with_tax = item.price + item.tax
         item_dict.update({"price_with_tax": price_with_tax})
     return item_dict
diff --git a/docs_src/body/tutorial002_py310.py b/docs_src/body/tutorial002_py310.py
index 8928b72b8..454c45c88 100644
--- a/docs_src/body/tutorial002_py310.py
+++ b/docs_src/body/tutorial002_py310.py
@@ -15,7 +15,7 @@ app = FastAPI()
 @app.post("/items/")
 async def create_item(item: Item):
     item_dict = item.dict()
-    if item.tax:
+    if item.tax is not None:
         price_with_tax = item.price + item.tax
         item_dict.update({"price_with_tax": price_with_tax})
     return item_dict