Merge pull request #123 from Learnware-LAMDA/fix_client_utils

[FIX] fix client util bug

learnware/client/utils.py

@@ -10,24 +10,18 @@ logger = get_module_logger(module_name="client_utils")
 
 
 def system_execute(args, timeout=None, env=None, stdout=subprocess.DEVNULL, stderr=subprocess.PIPE):
-    if env is None:
-        env = os.environ.copy()
-        pass
-
-    if isinstance(args, str):
-        pass
-    else:
-        args = " ".join(args)
-        pass
+    env = os.environ.copy() if env is None else env
+    args = args if isinstance(args, str) else " ".join(args)
 
     com_process = subprocess.run(args, stdout=stdout, stderr=stderr, timeout=timeout, env=env, shell=True)
 
     try:
         com_process.check_returncode()
     except subprocess.CalledProcessError as err:
-        errmsg = com_process.stderr.decode()
-        logger.warning(f"System Execute Error: {errmsg}")
-        raise Exception(errmsg)
+        if err.stderr is not None:
+            errmsg = err.stderr.decode()
+            logger.warning(f"System Execute Error: {errmsg}")
+        raise err
 
 
 def remove_enviroment(conda_env):