python 2.7 TypeError: environment can only contain strings

[davidovich]

I have this error on python 2.7 on Windows when at the resolve cycle.

The resolver.py module sets its unicode literals from the future import, and also wants to inject PIP_EXISTS_ACTION in the os.environ which does not accept unicode data as keys, nor values.

This makes subprocess calls issued in pip fail, because os.environ cannot contain unicode data.

Other projects have had this problem:

pallets/werkzeug#467
and
celery/django-celery#344

Other technique seen also on stackoverflow.

One suggestion is to remove the unicode_literals future import and this seems the easiest fix as it supports both python 2.7 and 3.

[davidovich]

As of 1.4 this is fixed and verified.
see 3a43904
@nvie this issue can be closed.

[nvie]

👍

[ibobak]

This is how I fixed this problem with jupyter kernel http://ihorbobak.com/index.php/2017/12/13/pyspark-kernel-for-jupyter-in-python-2-7-windows/ but I do believe yours can be fixed the same way