dels consists of all models and model infomorphisms. Every model has
an underlying type language and an underlying instance hypergraph.
Models are related through model infomorphisms. A model infomorphism
from source model to target model is a type language morphism between
the underlying type languages of source and target, a hypergraph
morphism between the underlying instance hypergraphs of source and
target, an entity classification infomorphism between the entity
classifications of source and target, an