为什么Python 3.6.1抛出AttributeError：模块’enum’没有属性’IntFlag’？

I just installed Python 3.6.1 for MacOS X

When I attempt to run the Console(or run anything with Python3), this error is thrown:

  AttributeError: module 'enum' has no attribute 'IntFlag'

$ /Library/Frameworks/Python.framework/Versions/3.6/bin/python3  
Failed to import the site module  
Traceback (most recent call last):  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 544, in <module>  
    main()  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 530, in main  
    known_paths = addusersitepackages(known_paths)  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 282, in addusersitepackages  
    user_site = getusersitepackages()  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 258, in getusersitepackages  
    user_base = getuserbase() # this will also set USER_BASE  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/site.py", line 248, in getuserbase  
    USER_BASE = get_config_var('userbase')  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/sysconfig.py", line 601, in get_config_var  
    return get_config_vars().get(name)  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/sysconfig.py", line 580, in get_config_vars  
    import _osx_support  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/_osx_support.py", line 4, in <module>  
    import re  
  File "/usr/local/Cellar/python3/3.6.1/Frameworks/Python.framework/Versions/3.6/lib/python3.6/re.py", line 142, in <module>  
    class RegexFlag(enum.IntFlag):  
AttributeError: module 'enum' has no attribute 'IntFlag'  

The class IntFlag exists within enum.py. So, why is the AttributeError being thrown?

It’s because your enum is not the standard library enum module. You probably have the package enum34 installed.

One way check if this is the case is to inspect the property enum.__file__

import enum
print(enum.__file__)  
# standard library location should be something like 
# /usr/local/lib/python3.6/enum.py

Since python 3.6 the enum34 library is no longer compatible with the standard library. The library is also unnecessary, so you can simply uninstall it.

pip uninstall -y enum34

If you need the code to run on python versions both <=3.4 and >3.4, you can try having as a requirement. It only installs enum34 for older versions of python without the standard library enum.

Not sure whether you still have this issue. I had a similar issue and I was able to resolve it simply by unsetting PYTHONPATH

$ unset PYTHONPATH

For me this error occured after installing of gcloud component app-engine-python in order to integrate into pycharm. Uninstalling the module helped, even if pycharm is now not uploading to app-engine.

If anyone coming here because of getting this error while running a google app engine Python 3.7 standard environment project in PyCharm then all you need to do is

• Make sure the configuration to run is for Flask, not Google App Engine configuration.
• Then disable Google App Engine support under Preferences >> Languages & Framework >> Google App Engine

The reason being as per this link

The overall goal is that your app should be fully portable and run in any standard Python environment. You write a standard Python app, not an App Engine Python app. As part of this shift, you are no longer required to use proprietary App Engine APIs and services for your app’s core functionality. At this time, App Engine APIs are not available in the Python 3.7 runtime.

I guess when we create a python 3.7 project in PyCharm as a Google app engine project it still tries to do the same way it does for a python2.7 app

DISCLAIMER: Please, @juanpa.arrivillaga, if you see this answer, feel free to write your own and I will remove this post.

@juanpa.arrivillaga had mentioned above:

Is there a file name enum.py in your working directory, by any chance?

This was the issue I encountered. I was not aware of the enum module on python at the time and had named my test file enum.py.

Since the file name is the module name, there was a conflict. More info on modules here: https://docs.python.org/2/tutorial/modules.html

Disabling “Google App Engine Support” in pycharm preferences fixed this issue for me.

Håken Lid’s answer helped solved my problem (thanks!) , in my case present in Python3.7 running Flask in a Docker container (FROM tiangolo/uwsgi-nginx-flask:python3.7-alpine3.7).

In my case, enum34 was being installed by another library (pip install smartsheet-python-sdk). For those coming with a similar Docker container problem, here is my final Dockerfile (stripped to the relevant lines):

FROM tiangolo/uwsgi-nginx-flask:python3.7-alpine3.7
...
RUN pip install -r requirements.txt
RUN pip uninstall -y enum34
...

In case you have to keep PYTHONPATH for both python2 and python3, you can write alias statements to set the proper PYTHONPATH in your bash_profile:

Hardcode your PYTHONPATH2, and PYTHONPATH3 variables in your ~/.bash_profile, and add the following aliases at the end of it:

alias python='export PYTHONPATH=${PYTHONPATH2};python'
alias python3='export PYTHONPATH=${PYTHONPATH3};python3'

My python (refers to python2) as I use python2 more often.

When ever I got this problem:

AttributeError: module ‘enum’ has no attribute ‘IntFlag’

simply first i run the command:

unset PYTHONPATH 

and then run my desired command then got success in that.

I did by using pip install <required-library> --ignore-installed enum34
Once your required library is installed, look for warnings during the build. I got an Error like this:
Using legacy setup.py install for future, since package 'wheel' is not installed
ERROR: pyejabberd 0.2.11 has requirement enum34==1.1.2, but you'll have enum34 1.1.10 which is incompatible.

To fix this issue now run the command: pip freeze | grep enum34. This will give you the version of the installed enum34. Now uninstall it by pip uninstall enum34 and reinstall the required version as
pip install "enum34==1.1.20"

I have Python 2 and Python 3 installed on my computer. For some strange reason I have in the sys.path of Python 3 also a path to the sitepackage library directory of Python2 when the re module is called. If I run Python 3 and import enum and print(enum.__file__) the system does not show this Python 2 path to site-packages. So a very rough and dirty hack is, to directly modify the module in which enum is imported (follow the traceback paths) and insert the following code just before importing enum:

import sys
for i, p in enumerate(sys.path):
    if "python27" in p.lower() or "python2.7" in p.lower(): sys.path.pop(i)
import enum

That solved my problem.

Installing version 1.1.8 of enum34 worked for me.

I was able to fix this by adding enum34 = “==1.1.8” to pyproject.toml. Apparently enum34 had a feature in v1.1.8 that avoided this error, but this regressed in v1.1.9+. This is just a workaround though. The better solution would be for packages to use environment markers so you don’t have to install enum34 at all unless needed.

Source: https://github.com/python-poetry/poetry/issues/1122

Even I had this issue while running python -m grpc_tools.protoc –version Had to set the PYTHONPATH till site-packages and shutdown all the command prompt windows and it worked. Hope it helps for gRPC users.

I had this problem in ubuntu20.04 in jupyterlab in my virtual env kernel with python3.8 and tensorflow 2.2.0. Error message was

 Traceback (most recent call last):
  File "/usr/lib/python2.7/runpy.py", line 174, in _run_module_as_main
    "__main__", fname, loader, pkg_name)
  File "/usr/lib/python2.7/runpy.py", line 72, in _run_code
    exec code in run_globals
  File "/home/hu-mka/.local/lib/python2.7/site-packages/ipykernel_launcher.py", line 15, in <module>
    from ipykernel import kernelapp as app
  File "/home/hu-mka/.local/lib/python2.7/site-packages/ipykernel/__init__.py", line 2, in <module>
    from .connect import *
  File "/home/hu-mka/.local/lib/python2.7/site-packages/ipykernel/connect.py", line 13, in <module>
    from IPython.core.profiledir import ProfileDir
  File "/home/hu-mka/.local/lib/python2.7/site-packages/IPython/__init__.py", line 48, in <module>
    from .core.application import Application
  File "/home/hu-mka/.local/lib/python2.7/site-packages/IPython/core/application.py", line 23, in <module>
    from traitlets.config.application import Application, catch_config_error
  File "/home/hu-mka/.local/lib/python2.7/site-packages/traitlets/__init__.py", line 1, in <module>
    from .traitlets import *
  File "/home/hu-mka/.local/lib/python2.7/site-packages/traitlets/traitlets.py", line 49, in <module>
    import enum
ImportError: No module named enum

problem was that in symbolic link in /usr/bin/python was pointing to python2. Solution:

cd /usr/bin/
sudo ln -sf python3 python

Hopefully Python 2 usage will drop off completely soon.

If you having this issue when running tests in PyCharm, make sure the second box is unchecked in the configurations.

If anyone is having this problem when trying to run Jupyter kernel from a virtualenv, just add correct PYTHONPATH to kernel.json of your virtualenv kernel (Python 3 in example):

{
 "argv": [
  "/usr/local/Cellar/python/3.6.5/bin/python3.6",
  "-m",
  "ipykernel_launcher",
  "-f",
  "{connection_file}"
 ],
 "display_name": "Python 3 (TensorFlow)",
 "language": "python",
 "env": {
     "PYTHONPATH":     "/Users/dimitrijer/git/mlai/.venv/lib/python3.6:/Users/dimitrijer/git/mlai/.venv/lib/python3.6/lib-dynload:/usr/local/Cellar/python/3.6.5/Frameworks/Python.framework/Versions/3.6/lib/python3.6:/Users/dimitrijer/git/mlai/.venv/lib/python3.6/site-packages"
}
}