Fix python version check

Author: Legrandin

lib/Crypto/SelfTest/Protocol/__init__.py

@@ -33,7 +33,7 @@ def get_tests(config={}):
     from Crypto.SelfTest.Protocol import test_SecretSharing
     tests += test_SecretSharing.get_tests(config=config)
 
-    if sys.version[0] >= 3:
+    if sys.version_info[0] >= 3:
         from Crypto.SelfTest.Protocol import test_HPKE
         tests += test_HPKE.get_tests(config=config)