Fix Python client TCPTransports not being able to close (#390)

* Fix Python client TCPTransports not being able to close

* Shutdown socket before close

* Replace unnecessary private import

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Co-authored-by: Thom van der Steenhoven <[email protected]>

Author: Thom747

erpc_python/erpc/transport.py

@@ -10,6 +10,8 @@
 import struct
 import socket
 import threading
+from socket import SHUT_RDWR
+
 from .crc16 import Crc16
 from .client import RequestError
 import time
@@ -166,7 +168,9 @@ def _serve(self):
             self._serverSockEventStart.set()
 
     def close(self):
-        self._serverSockEventStart.clear()
+        if self._isServer:
+            self._serverSockEventStart.clear()
+        self._sock.shutdown(SHUT_RDWR)
         self._sock.close()
         self._sock = None