fix(verifier): close file handle when computing checksum (#176)

Replace bare `open().read()` with a `with` block in
`get_file_checksum()` so the file descriptor is released
deterministically instead of waiting for garbage collection.

Apply the same cleanup to `setup.py` for `README.md` and `CHANGELOG.md`.

Co-authored-by: Tibor Šimko <tibor.simko@cern.ch>

Author: Stephen0512

AUTHORS.md

@@ -13,3 +13,4 @@ The list of contributors in alphabetical order:
 - [Pablo Saiz](https://github.com/psaiz)
 - [Parth Shandilya](https://github.com/ParthS007)
 - [Tibor Simko](https://orcid.org/0000-0001-7202-5803)
+- [Zhuohang Shen](https://github.com/Stephen0512)

cernopendata_client/verifier.py

@@ -2,7 +2,7 @@
 #
 # This file is part of cernopendata-client.
 #
-# Copyright (C) 2020, 2025 CERN.
+# Copyright (C) 2020, 2025, 2026 CERN.
 #
 # cernopendata-client is free software; you can redistribute it and/or modify
 # it under the terms of the GPLv3 license; see LICENSE file for more details.
@@ -38,9 +38,8 @@ def get_file_checksum(afile):
     :return: Adler32 checksum of file
     :rtype: str
     """
-    return "adler32:{:08x}".format(
-        zlib.adler32(open(afile, "rb").read(), 1) & 0xFFFFFFFF
-    )
+    with open(afile, "rb") as f:
+        return "adler32:{:08x}".format(zlib.adler32(f.read(), 1) & 0xFFFFFFFF)
 
 
 def get_file_info_local(recid):

setup.py

@@ -2,7 +2,7 @@
 #
 # This file is part of cernopendata-client.
 #
-# Copyright (C) 2019, 2020, 2021, 2022, 2023, 2024, 2025 CERN.
+# Copyright (C) 2019, 2020, 2021, 2022, 2023, 2024, 2025, 2026 CERN.
 #
 # cernopendata-client is free software; you can redistribute it and/or modify
 # it under the terms of the GPLv3 license; see LICENSE file for more details.
@@ -13,9 +13,10 @@
 
 from setuptools import setup
 
-readme = open("README.md").read()
-history = open("CHANGELOG.md").read()
-
+with open("README.md", "r") as f:
+    readme = f.read()
+with open("CHANGELOG.md", "r") as f:
+    history = f.read()
 
 extras_require = {
     "docs": [