pySim/transport: Use newly-defined ResTuple type

Let's use the newly-added ResTuple type annotation rather than
open-coding it everywhere.

Change-Id: I122589e8aec4bf66dc2e86d7602ebecb771dcb93
diff --git a/pySim/transport/calypso.py b/pySim/transport/calypso.py
index 4244b23..34fc646 100644
--- a/pySim/transport/calypso.py
+++ b/pySim/transport/calypso.py
@@ -21,11 +21,11 @@
 import socket
 import os
 
-from typing import Optional, Tuple
+from typing import Optional
 
 from pySim.transport import LinkBase
 from pySim.exceptions import *
-from pySim.utils import h2b, b2h, Hexstr, SwHexstr
+from pySim.utils import h2b, b2h, Hexstr, ResTuple
 
 
 class L1CTLMessage:
@@ -123,7 +123,7 @@
     def wait_for_card(self, timeout: Optional[int] = None, newcardonly: bool = False):
         pass  # Nothing to do really ...
 
-    def _send_apdu_raw(self, pdu: Hexstr) -> Tuple[Hexstr, SwHexstr]:
+    def _send_apdu_raw(self, pdu: Hexstr) -> ResTuple:
 
         # Request FULL reset
         req_msg = L1CTLMessageSIM(h2b(pdu))