def resolve_component_type(self, component_type):
        """
        Resolves references in the specified component type.

        @param component_type: Component type to be resolved.
        @type component_type: lems.model.component.ComponentType
        """
        
        # Resolve component type from base types if present.
        if component_type.extends:
            try:
                base_ct = self.component_types[component_type.extends]
            except:
                raise ModelError("Component type '{0}' trying to extend unknown component type '{1}'",
                                 component_type.name, component_type.extends)

            self.resolve_component_type(base_ct)
            self.merge_component_types(component_type, base_ct)
            component_type.types = set.union(component_type.types, base_ct.types)
            component_type.extends = None