string  usd_relationshipforwardedtargets(<stage>stage, string primpath, string name)
This function returns the list of forwarded targets of a given relationship. This is a convenience function to expand all the nested relationships, since a target in a relationship can be another relationship.
When running in the context of a node (such as a wrangle LOP), this argument can be an integer representing the input number (starting at 0) to read the stage from. The integer is equivalent to the string form referencing a particular input, e.g., "opinput:0".
The path to the primitive.
The relationship name.
List of forwarded targets in a relationship.
// Get the list of forwarded targets in cube's "some_relationship" relationship. string targets = usd_relationshipforwardedtargets(0, "/geo/cube", "some_relationship");