Why Python 3.6.1 throws AttributeError: module 'enum' has no attribute 'IntFlag'?

Question

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?

Answer 1

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 enum-compat as a requirement. It only installs enum34 for older versions of python without the standard library enum.