格式化模板输出
format方法的输出可以作为字符串、消息列表和ChatPromptValue获得。
作为字符串：
output = chat_prompt.format(input_language="English", output_language="French", text="I love programming.")
output
'System: You are a helpful assistant that translates English to French.\nHuman: I love programming.'
# 或者使用另一种方式
output_2 = chat_prompt.format_prompt(input_language="English", output_language="French", text="I love programming.").to_string()
assert output == output_2
作为ChatPromptValue：
chat_prompt.format_prompt(input_language="English", output_language="French", text="I love programming.")
ChatPromptValue(messages=[SystemMessage(content='You are a helpful assistant that translates English to French.', additional_kwargs={}), HumanMessage(content='I love programming.', additional_kwargs={})])
作为消息对象列表：
chat_prompt.format_prompt(input_language="English", output_language="French", text="I love programming.").to_messages()
[SystemMessage(content='You are a helpful assistant that translates English to French.', additional_kwargs={}),
HumanMessage(content='I love programming.', additional_kwargs={})]
