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Post function to enable you to assign an issue to a user within a specified role. When the transition is executed, the issue will be assigned to a user in a specified role. It is possible to assign the issue to a random user with that project role or to the user with that role who has been the assignee of the issue before.
Please bear in mind that if you use this post function within "Create Issue Transition", the post function should be placed right after the Creates the issue originally statement.
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