UMLR — Association::isDerived should be derived

In the L3 metamodel there are only 5 Associations with isDerived=true.
These are:
A_context_action
A_deployedElement_deploymentTarget
A_state_redefinitionContext
A_extension_metaclass
A_containedEdge_inGroup

However there are clearly many more Associations which are in practice derived - for example anything with an end which is a derivedUnion.
It seems that an Association should automatically be derived if one or both of its ends are derived.

Proposed resolution:
Make Association::isDerived itself a derived property (so it becomes Association::/isDerived)
The OCL for the derivation would be:
context Association isDerived = self.memberEnd->exists(isDerived)