Add type hints to routing folder

libp2p/routing/kademlia/kademlia_content_router.py

@@ -1,9 +1,14 @@
+from typing import (
+    Iterable,
+)
+
+from libp2p.peer.peerinfo import PeerInfo
 from libp2p.routing.interfaces import IContentRouting
 
 
 class KadmeliaContentRouter(IContentRouting):
 
-    def provide(self, cid, announce=True):
+    def provide(self, cid: bytes, announce: bool=True) -> None:
         """
         Provide adds the given cid to the content routing system. If announce is True,
         it also announces it, otherwise it is just kept in the local
@@ -12,7 +17,7 @@ class KadmeliaContentRouter(IContentRouting):
         # the DHT finds the closest peers to `key` using the `FIND_NODE` RPC
         # then sends a `ADD_PROVIDER` RPC with its own `PeerInfo` to each of these peers.
 
-    def find_provider_iter(self, cid, count):
+    def find_provider_iter(self, cid: bytes, count: int) -> Iterable[PeerInfo]:
         """
         Search for peers who are able to provide a given key
         returns an iterator of peer.PeerInfo