Use False instead of 0 in setblocking

* Add runtime check for IO Helper

* Remove repeated call to `sandwich()` in Listener

* Add typehint for Listener in Sandwich TCP test

* Use `False` instead of `0` in `setblocking`

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Co-authored-by: Duc Nguyen <[email protected]>
GitOrigin-RevId: e2ea7752735e1f810c98cf0736d870c9a1efa621

Author: 2 people

pysandwich/tunnel_test.py

@@ -142,8 +142,8 @@ def create_expired_client_conf(sw: Sandwich) -> tunnel.Context:
 
 def create_ios() -> tuple[SandwichIO.IO, SandwichIO.IO]:
     s1, s2 = socket.socketpair(family=socket.AF_UNIX, type=socket.SOCK_STREAM)
-    s1.setblocking(0)
-    s2.setblocking(0)
+    s1.setblocking(False)
+    s2.setblocking(False)
     return io_socket_wrap(s1), io_socket_wrap(s2)