Update tokenizer_config.json

tokenizer_config.json

@@ -1744,7 +1744,7 @@
     "<end_of_turn>"
   ],
   "bos_token": "<bos>",
-  "chat_template": "{{ bos_token }}{% if messages[0]['role'] == 'system' %}{{ '<start_of_turn>system\n' + messages[0]['content'] + '<end_of_turn>\n' }}{% endif %}{% for message in messages %}{% if (message['role'] == 'user') != ((loop.index0 + 1) % 2 == 0) %}{{ raise_exception('Conversation roles must alternate user/assistant/user/assistant/...') }}{% endif %}{% if (message['role'] == 'assistant') %}{% set role = 'model' %}{% else %}{% set role = message['role'] %}{% endif %}{% if message['role'] != 'system' %}{{ '<start_of_turn>' + role + '\n' + message['content'] | trim + '<end_of_turn>\n' }}{% endif %}{% endfor %}{% if add_generation_prompt %}{{'<start_of_turn>model\n'}}{% endif %}",
+  "chat_template": "{{ bos_token }}{% for message in messages %}{% if message['role'] not in ['user', 'assistant', 'system'] or (loop.index0 > 0 and message['role'] != 'system' and message['role'] == messages[loop.index0 - 1]['role']) %}{{ raise_exception('Invalid role or role sequence') }}{% endif %}{{ '<start_of_turn>' + message['role'] + '\n' + message['content'] | trim + '<end_of_turn>\n' if message['role'] != 'system' else message['content'] + '\n' }}{% endfor %}{% if add_generation_prompt %}{{ '<start_of_turn>model\n' }}{% endif %}",
   "clean_up_tokenization_spaces": false,
   "eos_token": "<eos>",
   "model_max_length": 2048,