add a conditiall branch for ensuring pass in python2 ut

Signed-off-by: Fei Su <fei.su@cloud.com>

scripts/mail-alarm

@@ -120,8 +120,15 @@ def load_mail_language(mail_language):
         mail_language_file = os.path.join(
             mail_language_pack_path, mail_language + ".json"
         )
+
+        # this conditional branch won't be executed, it's solely for the purpose of ensuring pass in python2 ut.
+        if sys.version_info.major == 2:
+            with open(mail_language_file, "r") as fileh:
+                return json.load(fileh, encoding="utf-8")
+
         with open(mail_language_file, encoding="utf-8") as fileh:
             return json.load(fileh)
+
     except IOError:
         log_err('Read mail language pack error:["%s"]' % (mail_language_file))
         return None