Turns out TransIP just uses webdav, so any python webdav wrapper will work
My example uses the webdavclient3 library to talk to stackstorage. To run the example export these environment variables:
export STACK_USERNAME=<your username>
export STACK_PASSWORD=<your password>
export STACK_HOSTNAME=https://<your name>.stackstorage.com
Run pip-install to pull in dependencies
pip install -e .
Run the example
transip_upload /tmp/localtestfile.txt /remotedestination.txt