Replace httpx and httpx-sse with httpx2 (#2972)

Co-authored-by: Max Isbey <224885523+maxisbey@users.noreply.github.com>

examples/snippets/clients/identity_assertion_client.py

@@ -16,7 +16,7 @@ to use.
 
 import asyncio
 
-import httpx
+import httpx2
 
 from mcp import ClientSession
 from mcp.client.auth.extensions.identity_assertion import IdentityAssertionOAuthProvider
@@ -66,7 +66,7 @@ async def main() -> None:
         scope="user",
     )
 
-    async with httpx.AsyncClient(auth=oauth_auth, follow_redirects=True) as http_client:
+    async with httpx2.AsyncClient(auth=oauth_auth, follow_redirects=True) as http_client:
         async with streamable_http_client("http://localhost:8001/mcp", http_client=http_client) as (read, write):
             async with ClientSession(read, write) as session:
                 await session.initialize()

examples/snippets/clients/oauth_client.py

@@ -9,7 +9,7 @@ cd to the `examples/snippets` directory and run:
 import asyncio
 from urllib.parse import parse_qs, urlparse
 
-import httpx
+import httpx2
 from pydantic import AnyUrl
 
 from mcp import ClientSession
@@ -72,7 +72,7 @@ async def main():
         callback_handler=handle_callback,
     )
 
-    async with httpx.AsyncClient(auth=oauth_auth, follow_redirects=True) as custom_client:
+    async with httpx2.AsyncClient(auth=oauth_auth, follow_redirects=True) as custom_client:
         async with streamable_http_client("http://localhost:8001/mcp", http_client=custom_client) as (read, write):
             async with ClientSession(read, write) as session:
                 await session.initialize()