Class Any {}
SimpleAttribute Natural {}
SimpleAttribute String {}
Class Class{
    lower_cardinality : Natural
    upper_cardinality : Natural
}
Association Association (Class, Class){
    name : String
    source_lower_cardinality : Natural
    source_upper_cardinality : Natural
    target_lower_cardinality : Natural
    target_upper_cardinality : Natural
}
Association Inheritance (Class, Class){}
Inheritance assoc_inh_class (Association, Class) {}
Inheritance class_inh_any (Class, Any) {}
