passlib 使用 bcrypt 哈希算法时：AttributeError: module ‘bcrypt‘ has no attribute ‘__about__‘_(trapped) error reading bcrypt version traceback (

先上终端虚拟环境下验证所用源码：

$ python3
Python 3.8.10 (default, Mar 11 2025, 17:45:31)
[GCC 9.4.0] on linux
Type \"help\", \"copyright\", \"credits\" or \"license\" for more information.
>>> from passlib.context import CryptContext
>>> pwd_context = CryptContext(schemes=[\'bcrypt\'],deprecated=\'auto\')
>>> hash_pass = pwd_context.hash(\'secret\')
(trapped) error reading bcrypt version
Traceback (most recent call last):
  File \"/data/Project/python/github_fastapi_project/fast_api_test_code/fast_api_test_code_env/lib/python3.8/site-packages/passlib/handlers/bcrypt.py\", line 620, in _load_backend_mixin
    version = _bcrypt.__about__.__version__
AttributeError: module \'bcrypt\' has no attribute \'__about__\'。

打印具体的属性信息（4.3.0版本）：

>>> import bcrypt
>>> print(dir(bcrypt))
[\'__all__\', \'__author__\', \'__builtins__\', \'__cached__\', \'__copyright__\', \'__doc__\', \'__email__\', \'__file__\', \'__license__\', \'__loader__\', \'__name__\', \'__package__\', \'__path__\', \'__spec__\', \'__summary__\', \'__title__\', \'__uri__\', \'__version__\', \'_bcrypt\', \'checkpw\', \'gensalt\', \'hashpw\', \'kdf\']没有\'__about__。

接着尝试更新到最新版本解决：

pip install --upgrade bcrypt

Requirement already up-to-date: bcrypt in ./fast_api_test_code_env/lib/python3.8/site-packages (4.3.0)
(fast_api_test_code_env)

已是最新的4.3.0版本。

之后去社区查找类似问题，根据提供的方案将版本降低到：

卸载最新版本：

pip uninstall bcrypt         
Found existing installation: bcrypt 4.3.0
Uninstalling bcrypt-4.3.0:
  Would remove:
    /data/Project/python/github_fastapi_project/fast_api_test_code/fast_api_test_code_env/lib/python3.8/site-packages/bcrypt-4.3.0.dist-info/*
    /data/Project/python/github_fastapi_project/fast_api_test_code/fast_api_test_code_env/lib/python3.8/site-packages/bcrypt/*
Proceed (y/n)? y
  Successfully uninstalled bcrypt-4.3.0
(fast_api_test_code_env)

安装指定版本：

$ pip install bcrypt==4.0.1

Collecting bcrypt==4.0.1
  Downloading bcrypt-4.0.1-cp36-abi3-manylinux_2_17_x86_64.manylinux2014_x86_64.whl (593 kB)
     |████████████████████████████████| 593 kB 1.0 MB/s
Installing collected packages: bcrypt
Successfully installed bcrypt-4.0.1
(fast_api_test_code_env)

接着查看安装的版本：

$ python3
Python 3.8.10 (default, Mar 11 2025, 17:45:31)
[GCC 9.4.0] on linux
Type \"help\", \"copyright\", \"credits\" or \"license\" for more information.
>>> import bcrypt
>>> print(dir(bcrypt))
[\'__about__\', \'__all__\', \'__author__\', \'__builtins__\', \'__cached__\', \'__copyright__\', \'__doc__\', \'__email__\', \'__file__\', \'__license__\', \'__loader__\', \'__name__\', \'__package__\', \'__path__\', \'__spec__\', \'__summary__\', \'__title__\', \'__uri__\', \'__version__\', \'_bcrypt\', \'absolute_import\', \'checkpw\', \'division\', \'gensalt\', \'hashpw\', \'hmac\', \'kdf\', \'os\', \'warnings\']
>>> exit
Use exit() or Ctrl-D (i.e. EOF) to exit
>>>