diff --git a/tools/ci/ci_fetch_submodule.py b/tools/ci/ci_fetch_submodule.py
index 3ce2285c4..62401a669 100644
--- a/tools/ci/ci_fetch_submodule.py
+++ b/tools/ci/ci_fetch_submodule.py
@@ -27,6 +27,7 @@ class SubModule(object):
 
     def _get_commit_id(self, path):
         output = subprocess.check_output(["git", "ls-tree", "HEAD", path])
+        output = output.decode()
         # example output: 160000 commit d88a262fbdf35e5abb372280eb08008749c3faa0	components/esp_wifi/lib
         match = self.GIT_LS_TREE_OUTPUT_PATTERN.search(output)
         return match.group(1)
diff --git a/tools/ci/python_packages/gitlab_api.py b/tools/ci/python_packages/gitlab_api.py
index d4fc4600f..d2e6abe7f 100644
--- a/tools/ci/python_packages/gitlab_api.py
+++ b/tools/ci/python_packages/gitlab_api.py
@@ -15,7 +15,7 @@ class Gitlab(object):
         config_data_from_env = os.getenv("PYTHON_GITLAB_CONFIG")
         if config_data_from_env:
             # prefer to load config from env variable
-            with tempfile.NamedTemporaryFile(delete=False) as temp_file:
+            with tempfile.NamedTemporaryFile("w", delete=False) as temp_file:
                 temp_file.write(config_data_from_env)
             config_files = [temp_file.name]
         else: