chore(samples): add comment about out-of-order requests (#347)

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Fixes #<issue_number_goes_here> 🦕

Author: kchertenko

packages/google-cloud-retail/samples/interactive-tutorials/product/add_fulfillment_places.py

@@ -44,6 +44,10 @@ def get_add_fulfillment_request(
     add_fulfillment_request.place_ids = [place_id]
     add_fulfillment_request.allow_missing = True
 
+    # To send an out-of-order request assign the invalid add_time here:
+    # import datetime
+    # add_fulfillment_request.add_time = datetime.datetime.now() - datetime.timedelta(days=1)
+
     print("---add fulfillment request---")
     print(add_fulfillment_request)
 
@@ -69,4 +73,3 @@ async def add_places(product_name: str):
 create_product(product_id)
 
 asyncio.run(add_places(product_name))
-# [END retail_add_fulfillment_places]

packages/google-cloud-retail/samples/interactive-tutorials/product/remove_fulfillment_places.py

@@ -39,6 +39,10 @@ def get_remove_fulfillment_request(
     remove_fulfillment_request.place_ids = [store_id]
     remove_fulfillment_request.allow_missing = True
 
+    # To send an out-of-order request assign the invalid remove_time here:
+    # import datetime
+    # remove_fulfillment_request.remove_time = datetime.datetime.now() - datetime.timedelta(days=1)
+
     print("---remove fulfillment request---")
     print(remove_fulfillment_request)
 
@@ -64,4 +68,3 @@ async def remove_places(product_name: str):
 product = create_product(product_id)
 
 asyncio.run(remove_places(product.name))
-# [END retail_remove_fulfillment_places]

packages/google-cloud-retail/samples/interactive-tutorials/product/set_inventory.py

@@ -73,6 +73,10 @@ def get_set_inventory_request(product_name: str) -> SetInventoryRequest:
     set_inventory_request.allow_missing = True
     set_inventory_request.set_mask = set_mask
 
+    # To send an out-of-order request assign the invalid set_time here:
+    # import datetime
+    # set_inventory_request.set_time = datetime.datetime.now() - datetime.timedelta(days=1)
+
     print("---set inventory request---")
     print(set_inventory_request)
 
@@ -99,4 +103,3 @@ async def set_inventory_and_remove_product(product_name: str):
 
 product = create_product(product_id)
 asyncio.run(set_inventory_and_remove_product(product.name))
-# [END retail_set_inventory]