partial() — langchain Function Reference

Architecture documentation for the partial() function in chat.py from the langchain codebase.

Function python PromptManagement ChatTemplates calls 2 called by 1

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PromptManagement→ ChatTemplates→ partial() — langchain Function Reference

Dependency Diagram

graph TD
  490adae9_6c8b_f224_cfeb_133ca6ea29c8["partial()"]
  6be4a9a5_5fe4_e64f_c374_e63767576bf6["ChatPromptTemplate"]
  490adae9_6c8b_f224_cfeb_133ca6ea29c8 -->|defined in| 6be4a9a5_5fe4_e64f_c374_e63767576bf6
  05fbd76f_5319_5d90_fd32_8ae595f01924["__add__()"]
  05fbd76f_5319_5d90_fd32_8ae595f01924 -->|calls| 490adae9_6c8b_f224_cfeb_133ca6ea29c8
  868943e8_3763_c08b_6ee7_cd2801948c3a["from_messages()"]
  490adae9_6c8b_f224_cfeb_133ca6ea29c8 -->|calls| 868943e8_3763_c08b_6ee7_cd2801948c3a
  a912d932_8157_994e_b37d_ed55e4821d34["format_messages()"]
  490adae9_6c8b_f224_cfeb_133ca6ea29c8 -->|calls| a912d932_8157_994e_b37d_ed55e4821d34
  style 490adae9_6c8b_f224_cfeb_133ca6ea29c8 fill:#6366f1,stroke:#818cf8,color:#fff

Relationship Graph

Source Code

libs/core/langchain_core/prompts/chat.py lines 1225–1258

    def partial(self, **kwargs: Any) -> ChatPromptTemplate:
        """Get a new `ChatPromptTemplate` with some input variables already filled in.

        Args:
            **kwargs: Keyword arguments to use for filling in template variables.

                Ought to be a subset of the input variables.

        Returns:
            A new `ChatPromptTemplate`.

        Example:
            ```python
            from langchain_core.prompts import ChatPromptTemplate

            template = ChatPromptTemplate.from_messages(
                [
                    ("system", "You are an AI assistant named {name}."),
                    ("human", "Hi I'm {user}"),
                    ("ai", "Hi there, {user}, I'm {name}."),
                    ("human", "{input}"),
                ]
            )
            template2 = template.partial(user="Lucy", name="R2D2")

            template2.format_messages(input="hello")
            ```
        """
        prompt_dict = self.__dict__.copy()
        prompt_dict["input_variables"] = list(
            set(self.input_variables).difference(kwargs)
        )
        prompt_dict["partial_variables"] = {**self.partial_variables, **kwargs}
        return type(self)(**prompt_dict)