Template formats

PromptTemplate by default uses Python f-string as its template format. However, it can also use other formats like jinja2, specified through the template_format argument.

To use the jinja2 template:

from langchain.prompts import PromptTemplate

jinja2_template = "Tell me a {{ adjective }} joke about {{ content }}"
prompt = PromptTemplate.from_template(jinja2_template, template_format="jinja2")

prompt.format(adjective="funny", content="chickens")
# Output: Tell me a funny joke about chickens.

To use the Python f-string template:

from langchain.prompts import PromptTemplate

fstring_template = """Tell me a {adjective} joke about {content}"""
prompt = PromptTemplate.from_template(fstring_template)

prompt.format(adjective="funny", content="chickens")
# Output: Tell me a funny joke about chickens.

Currently, only jinja2 and f-string are supported. For other formats, kindly raise an issue on the Github page.