As I understand it, the only JSON option right now is the output of (what was previously) nvme list -o json -v, with no option to get the original output back. Our automation is using something like ...

CNTLIN=input-control-SAS-data-set specifies a SAS data set from which PROC FORMAT builds informats and formats. CNTLIN= builds formats and informats without using a VALUE, PICTURE, or INVALUE ...