In what system and where?
I'm taking a guess that the target is Jira, but where are you trying to do this? As you're saying JSON, I'm guessing REST, in which case, you can't because it's not available yet (unless I've misunderstood https://docs.atlassian.com/jira/REST/latest/ ).
But I'm really not sure, because there's not enough information in your question.
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