Every time I try to upgrade Anaconda packages (version 3.15.1) on my Mac (OS X 10.10.4), I get the following message:
Error in sitecustomize; set PYTHONVERBOSE for traceback: KeyError: 'PYTHONPATH'
The rest of the update process is working fine, but I would like to find out what causes this message and how to delete it.
Set the PYTHONVERBOSE environment variable as indicated in the error message:
PYTHONVERBOSE=1 conda update --all
This should give you a complete trace, which should tell you which file this error comes from.