code: def test_codellama_prompt_format():
      messages = [
          {"role": "system", "content": "You are a good bot"},
          {"role": "user", "content": "Hey, how's it going?"},
      ]
      expected_prompt = "<s>[INST] <<SYS>>\nYou are a good bot\n<</SYS>>\n [/INST]\n[INST] Hey, how's it going? [/INST]\n"
      assert llama_2_chat_pt(messages) == expected_prompt
  
imports: import sys
  import os
  from litellm import completion
  from litellm.llms.prompt_templates.factory import anthropic_pt, claude_2_1_pt, llama_2_chat_pt
label_desc: Use image node_id 1 for calling a global function with example usage: test_codellama_prompt_format() without return types