[Python] Error with LangChain ChatPromptTemplate.from_messages

As shown in LangChain Quickstart, I am trying the following Python code:

from langchain.prompts.chat import ChatPromptTemplate
template = "You are a helpful assistant that translates {input_language} to {output_language}."
human_template = "{text}"

chat_prompt = ChatPromptTemplate.from_messages([
("system", template),
("human", human_template),
])

chat_prompt.format_messages(input_language="English", output_language="French", text="I love programming.")


But when I run the above code, I get the following error:

Traceback (most recent call last):
File "/home/yser364/Projets/SinappsIrdOpenaiQA/promptWorkout.py", line 6, in <module>
chat_prompt = ChatPromptTemplate.from_messages([
File "/home/yser364/.local/lib/python3.10/site-packages/langchain/prompts/chat.py", line 220, in from_messages
return cls(input_variables=list(input_vars), messages=messages)
File "/home/yser364/.local/lib/python3.10/site-packages/langchain/load/serializable.py", line 64, in __init__
super().__init__(**kwargs)
File "pydantic/main.py", line 341, in pydantic.main.BaseModel.__init__
pydantic.error_wrappers.ValidationError: 4 validation errors for ChatPromptTemplate
messages -> 0
value is not a valid dict (type=type_error.dict)
messages -> 0
value is not a valid dict (type=type_error.dict)
messages -> 1
value is not a valid dict (type=type_error.dict)
messages -> 1
value is not a valid dict (type=type_error.dict)


I use Python 3.10.12.

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