community: Add you.com tool, add async to retriever, add async testing, add You tool doc (#18032)

- **Description:** finishes adding the you.com functionality including:
    - add async functions to utility and retriever
    - add the You.com Tool
    - add async testing for utility, retriever, and tool
    - add a tool integration notebook page
- **Dependencies:** any dependencies required for this change
- **Twitter handle:** @scottnath

libs/community/langchain_community/tools/you/tool.py

@@ -0,0 +1,43 @@
+from typing import List, Optional, Type
+
+from langchain_core.callbacks import (
+    AsyncCallbackManagerForToolRun,
+    CallbackManagerForToolRun,
+)
+from langchain_core.documents import Document
+from langchain_core.pydantic_v1 import BaseModel, Field
+from langchain_core.tools import BaseTool
+
+from langchain_community.utilities.you import YouSearchAPIWrapper
+
+
+class YouInput(BaseModel):
+    query: str = Field(description="should be a search query")
+
+
+class YouSearchTool(BaseTool):
+    """Tool that searches the you.com API"""
+
+    name = "you_search"
+    description = (
+        "The YOU APIs make LLMs and search experiences more factual and"
+        "up to date with realtime web data."
+    )
+    args_schema: Type[BaseModel] = YouInput
+    api_wrapper: YouSearchAPIWrapper = Field(default_factory=YouSearchAPIWrapper)
+
+    def _run(
+        self,
+        query: str,
+        run_manager: Optional[CallbackManagerForToolRun] = None,
+    ) -> List[Document]:
+        """Use the you.com tool."""
+        return self.api_wrapper.results(query)
+
+    async def _arun(
+        self,
+        query: str,
+        run_manager: Optional[AsyncCallbackManagerForToolRun] = None,
+    ) -> List[Document]:
+        """Use the you.com tool asynchronously."""
+        return await self.api_wrapper.results_async(query)