update category prefix according to docs

src/llama_cookbook/data/llama_guard/README.md

@@ -50,7 +50,7 @@ guidelines = Guidelines(
         Category(name="Location",
                  description="Information about where someone lives or works")
     ],
-    category_code_prefix="O"
+    category_code_prefix="S"
 )
 ```
 

src/llama_cookbook/data/llama_guard/finetuning_data_formatter.py

@@ -17,7 +17,7 @@ class Category:
 @dataclass
 class Guidelines:
     categories: Sequence[Category]
-    category_code_prefix: str = "O"
+    category_code_prefix: str = "S"
 
 
 class ExplanationPosition(Enum):

src/llama_cookbook/data/llama_guard/finetuning_data_formatter_example.py

@@ -11,7 +11,7 @@ guidelines = Guidelines(
         Category(name="Location",
                  description="Information about where someone lives or works")
     ],
-    category_code_prefix="O"
+    category_code_prefix="S"
 )
 
 training_examples = [

src/llama_cookbook/datasets/toxicchat_dataset.py

@@ -60,7 +60,7 @@ def get_llamaguard_toxicchat_dataset(dataset_config, tokenizer, split, return_js
     
     guidelines = Guidelines(
         categories=LLAMA_GUARD_3_CATEGORY,
-        category_code_prefix="O")
+        category_code_prefix="S")
     
     # Setting up configs
     llama_guard_prompt_configs = LlamaGuardPromptConfigs(

src/tests/test_finetuning_data_formatter.py

@@ -38,7 +38,7 @@ class FinetuningDataFormatterTests(unittest.TestCase):
                     Category(name="cat Y", description="cat Y description"),
                     Category(name="cat Z", description="cat Z description"),
                 ],
-                category_code_prefix="O",
+                category_code_prefix="S",
             ),
             llama_guard_prompt_configs=LlamaGuardPromptConfigs(
                 instructions_format_string=f"""[INST] Task: Check if there is unsafe content in '{agent_type_to_check}' messages in conversations according our safety policy with the below categories.