Dataverse installations each issue their own API token (unlike Zenodo/OSF,
which are single services) – a token from dataverse.harvard.edu is
meaningless to dataverse.nl. Tokens are therefore stored per host.
Details
Create a token by signing in to the installation, opening your account page, and selecting "API Token".
Store it as an environment variable named DATAVERSE_PAT_<HOST>, with the
host uppercased and every . replaced by _ (e.g.
DATAVERSE_PAT_DATAVERSE_HARVARD_EDU), so it is read every time R starts.
