from langchain_core.prompts import ChatPromptTemplate

prompt = ChatPromptTemplate.from_messages(
    [
        ("system", "You write release notes for infrastructure teams."),
        (
            "human",
            "Summarize {change} for {audience} in no more than {sentences} sentences.",
        ),
    ]
)

values = {
    "change": "automated snapshot cleanup",
    "audience": "database operators",
    "sentences": 2,
}
prompt_value = prompt.invoke(values)

print("Required variables:", ", ".join(prompt.input_variables))
for message in prompt_value.to_messages():
    print(f"{message.type}: {message.content}")