An import (DMN 1.6, 6.3.3): the model with namespace is available under name. location_uri is a hint for a
Dmn.Resolver and is never opened by itself. It is a URI reference (RFC 3986): a relative one is resolved against the base_uri of the
model that has the import, which is what the resolver is given the importer for. An empty name imports into the default namespace
of the importing model.