Click will abort further execution because Python 3 was configured to use ASCII as encoding for the environment

If you are trying to execute tests case you must set the following environment variables each time:

export LC_ALL=en_US.utf-8
export LANG=en_US.utf-8

Doing this each time will resolve the error.

It may also be possible to set this in your IDE run configuration as

LC_ALL=en_US.UTF-8;LANG=en_US.UTF-8

For example see the following setting in PyCharm 2016: