Fixed a link typo /-/route -> /-/routes. and change endpoint format (#6186)

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Fixes a link typo from `/-/route` to `/-/routes`. 
and change endpoint format
from `f"{self.anyscale_service_url}/{self.anyscale_service_route}"` to
`f"{self.anyscale_service_url}{self.anyscale_service_route}"`
Also adding documentation about the format of the endpoint
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---------

Co-authored-by: Harrison Chase <hw.chase.17@gmail.com>

docs/extras/modules/model_io/models/llms/integrations/anyscale.ipynb

@@ -1,6 +1,7 @@
 {
  "cells": [
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "9597802c",
    "metadata": {},
@@ -9,7 +10,9 @@
     "\n",
     "[Anyscale](https://www.anyscale.com/) is a fully-managed [Ray](https://www.ray.io/) platform, on which you can build, deploy, and manage scalable AI and Python applications\n",
     "\n",
-    "This example goes over how to use LangChain to interact with `Anyscale` [service](https://docs.anyscale.com/productionize/services-v2/get-started)"
+    "This example goes over how to use LangChain to interact with `Anyscale` [service](https://docs.anyscale.com/productionize/services-v2/get-started). \n",
+    "\n",
+    "It will send the requests to Anyscale Service endpoint, which is concatenate `ANYSCALE_SERVICE_URL` and `ANYSCALE_SERVICE_ROUTE`, with a token defined in `ANYSCALE_SERVICE_TOKEN`"
    ]
   },
   {
@@ -96,6 +99,7 @@
    ]
   },
   {
+   "attachments": {},
    "cell_type": "markdown",
    "id": "42f05b34-1a44-4cbd-8342-35c1572b6765",
    "metadata": {},

langchain/llms/anyscale.py

@@ -59,12 +59,17 @@ class Anyscale(LLM):
         anyscale_service_token = get_from_dict_or_env(
             values, "anyscale_service_token", "ANYSCALE_SERVICE_TOKEN"
         )
+        if anyscale_service_url.endswith("/"):
+            anyscale_service_url = anyscale_service_url[:-1]
+        if not anyscale_service_route.startswith("/"):
+            anyscale_service_route = "/" + anyscale_service_route
         try:
-            anyscale_service_endpoint = f"{anyscale_service_url}/-/route"
+            anyscale_service_endpoint = f"{anyscale_service_url}/-/routes"
             headers = {"Authorization": f"Bearer {anyscale_service_token}"}
             requests.get(anyscale_service_endpoint, headers=headers)
         except requests.exceptions.RequestException as e:
             raise ValueError(e)
+
         values["anyscale_service_url"] = anyscale_service_url
         values["anyscale_service_route"] = anyscale_service_route
         values["anyscale_service_token"] = anyscale_service_token
@@ -102,7 +107,7 @@ class Anyscale(LLM):
         """
 
         anyscale_service_endpoint = (
-            f"{self.anyscale_service_url}/{self.anyscale_service_route}"
+            f"{self.anyscale_service_url}{self.anyscale_service_route}"
         )
         headers = {"Authorization": f"Bearer {self.anyscale_service_token}"}
         body = {"prompt": prompt}