{{ bos_token }}
{%- set loop_messages = messages -%}
{%- for message in loop_messages -%}
    {%- if message['role'] == 'system' -%}
        {%- set role = 'user' -%}
    {%- elif message['role'] == 'assistant' -%}
        {%- set role = 'model' -%}
    {%- else -%}
        {%- set role = message['role'] -%}
    {%- endif -%}
    
    {%- if (role == 'user') != (loop.index0 % 2 == 0) -%}
        {{ raise_exception("Conversation roles must alternate user/assistant/user/assistant/...") }}
    {%- endif -%}
    
    {{ '<start_of_turn>' + role + '\n' }}
    {%- if message['content'] is string -%}
        {{ message['content'] | trim }}
    {%- elif message['content'] is iterable -%}
        {%- for item in message['content'] -%}
            {%- if item['type'] == 'image' -%}
                {{ '<start_of_image>' }}
            {%- elif item['type'] == 'text' -%}
                {{ item['text'] | trim }}
            {%- endif -%}
        {%- endfor -%}
    {%- else -%}
        {{ raise_exception("Invalid content type") }}
    {%- endif -%}
    {{ '<end_of_turn>\n' }}
{%- endfor -%}
{%- if add_generation_prompt -%}
    {{'<start_of_turn>model\n'}}
{%- endif -%}