Add support for wikipedia's lang parameter (langchain-ai#3383)

Allow to hange the language of the wikipedia API being requested.

Co-authored-by: zhuohui <zhuohui@datastory.com.cn>

Author: zczhuohuo

langchain/agents/load_tools.py

@@ -240,7 +240,7 @@ def _get_human_tool(**kwargs: Any) -> BaseTool:
     "google-serper": (_get_google_serper, ["serper_api_key"]),
     "serpapi": (_get_serpapi, ["serpapi_api_key", "aiosession"]),
     "searx-search": (_get_searx_search, ["searx_host", "engines", "aiosession"]),
-    "wikipedia": (_get_wikipedia, ["top_k_results"]),
+    "wikipedia": (_get_wikipedia, ["top_k_results", "lang"]),
     "human": (_get_human_tool, ["prompt_func", "input_func"]),
 }
 

langchain/utilities/wikipedia.py

@@ -17,6 +17,7 @@ class WikipediaAPIWrapper(BaseModel):
 
     wiki_client: Any  #: :meta private:
     top_k_results: int = 3
+    lang: str = "en"
 
     class Config:
         """Configuration for this pydantic object."""
@@ -29,6 +30,7 @@ def validate_environment(cls, values: Dict) -> Dict:
         try:
             import wikipedia
 
+            wikipedia.set_lang(values["lang"])
             values["wiki_client"] = wikipedia
         except ImportError:
             raise ValueError(