Source code for langchain.prompts.loading
"""Load prompts."""
import json
import logging
from pathlib import Path
from typing import Callable, Dict, Union
import yaml
from langchain.prompts.few_shot import FewShotPromptTemplate
from langchain.prompts.prompt import PromptTemplate
from langchain.schema import BaseLLMOutputParser, BasePromptTemplate, StrOutputParser
from langchain.utils.loading import try_load_from_hub
URL_BASE = "https://raw.githubusercontent.com/hwchase17/langchain-hub/master/prompts/"
logger = logging.getLogger(__name__)
[docs]def load_prompt_from_config(config: dict) -> BasePromptTemplate:
    """Load prompt from Config Dict."""
    if "_type" not in config:
        logger.warning("No `_type` key found, defaulting to `prompt`.")
    config_type = config.pop("_type", "prompt")
    if config_type not in type_to_loader_dict:
        raise ValueError(f"Loading {config_type} prompt not supported")
    prompt_loader = type_to_loader_dict[config_type]
    return prompt_loader(config)
def _load_template(var_name: str, config: dict) -> dict:
    """Load template from the path if applicable."""
    # Check if template_path exists in config.
    if f"{var_name}_path" in config:
        # If it does, make sure template variable doesn't also exist.
        if var_name in config:
            raise ValueError(
                f"Both `{var_name}_path` and `{var_name}` cannot be provided."
            )
        # Pop the template path from the config.
        template_path = Path(config.pop(f"{var_name}_path"))
        # Load the template.
        if template_path.suffix == ".txt":
            with open(template_path) as f: