Fix Python AttributeError: module ‘lib’ has no attribute ‘OpenSSL_add_all_algorithms’

I use Python 3.9 in the base environment and encountered the error when creating a new virtual environment with Python 3.7:

conda create -n myenv python=3.7 -c conda-forge

The complete error message is as below:

Traceback (most recent call last):
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/exceptions.py", line 1082, in __call__
    return func(*args, **kwargs)
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/cli/main.py", line 87, in _main
    exit_code = do_call(args, p)
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/cli/conda_argparse.py", line 82, in do_call
    module = import_module(relative_mod, __name__.rsplit('.', 1)[0])
  File "/Users/user/opt/anaconda3/lib/python3.9/importlib/__init__.py", line 127, in import_module
    return _bootstrap._gcd_import(name[level:], package, level)
  File "<frozen importlib._bootstrap>", line 1030, in _gcd_import
  File "<frozen importlib._bootstrap>", line 1007, in _find_and_load
  File "<frozen importlib._bootstrap>", line 986, in _find_and_load_unlocked
  File "<frozen importlib._bootstrap>", line 680, in _load_unlocked
  File "<frozen importlib._bootstrap_external>", line 850, in exec_module
  File "<frozen importlib._bootstrap>", line 228, in _call_with_frames_removed
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/cli/main_create.py", line 10, in <module>
    from .install import install
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/cli/install.py", line 19, in <module>
    from ..core.index import calculate_channel_urls, get_index
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/core/index.py", line 13, in <module>
    from .package_cache_data import PackageCacheData
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/core/package_cache_data.py", line 14, in <module>
    from .path_actions import CacheUrlAction, ExtractPackageAction
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/core/path_actions.py", line 29, in <module>
    from ..gateways.connection.download import download
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/gateways/connection/download.py", line 14, in <module>
    from .session import CondaSession
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/gateways/connection/session.py", line 13, in <module>
    from .adapters.s3 import S3Adapter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/gateways/connection/adapters/s3.py", line 12, in <module>
    import boto3
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/boto3/__init__.py", line 17, in <module>
    from boto3.session import Session
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/boto3/session.py", line 17, in <module>
    import botocore.session
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/session.py", line 26, in <module>
    import botocore.client
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/client.py", line 15, in <module>
    from botocore import waiter, xform_name
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/waiter.py", line 18, in <module>
    from botocore.docs.docstring import WaiterDocstring
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/__init__.py", line 15, in <module>
    from botocore.docs.service import ServiceDocumenter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/service.py", line 14, in <module>
    from botocore.docs.client import ClientDocumenter, ClientExceptionsDocumenter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/client.py", line 14, in <module>
    from botocore.docs.example import ResponseExampleDocumenter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/example.py", line 13, in <module>
    from botocore.docs.shape import ShapeDocumenter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/shape.py", line 19, in <module>
    from botocore.utils import is_json_value_header
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/utils.py", line 34, in <module>
    import botocore.httpsession
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/httpsession.py", line 34, in <module>
    from urllib3.contrib.pyopenssl import orig_util_SSLContext as SSLContext
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/urllib3/contrib/pyopenssl.py", line 50, in <module>
    import OpenSSL.SSL
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/OpenSSL/__init__.py", line 8, in <module>
    from OpenSSL import crypto, SSL
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/OpenSSL/crypto.py", line 3279, in <module>
    _lib.OpenSSL_add_all_algorithms()
AttributeError: module 'lib' has no attribute 'OpenSSL_add_all_algorithms'
During handling of the above exception, another exception occurred:
Traceback (most recent call last):
  File "/Users/user/opt/anaconda3/bin/conda", line 13, in <module>
    sys.exit(main())
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/cli/main.py", line 155, in main
    return conda_exception_handler(_main, *args, **kwargs)
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/exceptions.py", line 1374, in conda_exception_handler
    return_value = exception_handler(func, *args, **kwargs)
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/exceptions.py", line 1085, in __call__
    return self.handle_exception(exc_val, exc_tb)
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/exceptions.py", line 1129, in handle_exception
    return self.handle_unexpected_exception(exc_val, exc_tb)
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/exceptions.py", line 1140, in handle_unexpected_exception
    self.print_unexpected_error_report(error_report)
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/exceptions.py", line 1210, in print_unexpected_error_report
    from .cli.main_info import get_env_vars_str, get_main_info_str
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/cli/main_info.py", line 19, in <module>
    from ..core.index import _supplement_index_with_system
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/core/index.py", line 13, in <module>
    from .package_cache_data import PackageCacheData
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/core/package_cache_data.py", line 14, in <module>
    from .path_actions import CacheUrlAction, ExtractPackageAction
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/core/path_actions.py", line 29, in <module>
    from ..gateways.connection.download import download
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/gateways/connection/download.py", line 14, in <module>
    from .session import CondaSession
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/gateways/connection/session.py", line 13, in <module>
    from .adapters.s3 import S3Adapter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/conda/gateways/connection/adapters/s3.py", line 12, in <module>
    import boto3
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/boto3/__init__.py", line 17, in <module>
    from boto3.session import Session
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/boto3/session.py", line 17, in <module>
    import botocore.session
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/session.py", line 26, in <module>
    import botocore.client
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/client.py", line 15, in <module>
    from botocore import waiter, xform_name
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/waiter.py", line 18, in <module>
    from botocore.docs.docstring import WaiterDocstring
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/__init__.py", line 15, in <module>
    from botocore.docs.service import ServiceDocumenter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/service.py", line 14, in <module>
    from botocore.docs.client import ClientDocumenter, ClientExceptionsDocumenter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/client.py", line 14, in <module>
    from botocore.docs.example import ResponseExampleDocumenter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/example.py", line 13, in <module>
    from botocore.docs.shape import ShapeDocumenter
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/docs/shape.py", line 19, in <module>
    from botocore.utils import is_json_value_header
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/utils.py", line 34, in <module>
    import botocore.httpsession
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/botocore/httpsession.py", line 34, in <module>
    from urllib3.contrib.pyopenssl import orig_util_SSLContext as SSLContext
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/urllib3/contrib/pyopenssl.py", line 50, in <module>
    import OpenSSL.SSL
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/OpenSSL/__init__.py", line 8, in <module>
    from OpenSSL import crypto, SSL
  File "/Users/user/opt/anaconda3/lib/python3.9/site-packages/OpenSSL/crypto.py", line 3279, in <module>
    _lib.OpenSSL_add_all_algorithms()
AttributeError: module 'lib' has no attribute 'OpenSSL_add_all_algorithms'
Note: you may need to restart the kernel to use updated packages.

The Root Cause And How To Fix It

After reading many posts, it seems that the root cause is the conflicts between pyOpenSSL and Cryptography. The solution is to install pyOpenSSL with the command, which will automatically install cryptography 38.0.4.

pip install pyOpenSSL=='22.1.0'