Format output correctly from the command line and error correctly

[sHedC]

I tried using the rc9 of the python tool, but it produces invalid json with the --pretty option.
Instead of:

{"1061_1": {"A_1": "17.6", "A_10": "-11.0"}}

it produces

1061_1: {"A_1": "17.6", "A_10": "-11.0"}

And also the warnings are going to stdout instead of stderr, so messing with the useful data...