Need example on get_xxx functions using HOST keyword

In section B1 we introduced the HOST keyword with a description on how orchestrators need to evaluate it when implementing itl however, it is a somewhat complex concept and does not have an example.

Description:
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A TOSCA orchestrator will interpret this keyword to refer to the all nodes that “host” the node using this reference (i.e., as identified by its HostedOn relationship).

Specifically, TOSCA orchestrators that encounter this keyword when evaluating the get_attribute or get_property functions SHALL search each node along the “HostedOn” relationship chain starting at the immediate node that hosts the node where the function was evaluated (and then that node’s host node, and so forth) until a match is found or the “HostedOn” relationship chain ends.