I'm sure I will find a work-around.
I posted it for other who will face the same issue as me.
There are many who uses cloud storage but not many work with PB size files. This will likely to change in the near future as more and more company start to process huge amount of data.

I'm not sure what you mean by designing an API. I think you sale it up for no need. It simply add of optional parameter which will trigger compression of gzip. That's it. Nothing sophisticated. 

Something like:

json.dumps(data, outfile, sort_keys=True,compression='gzip')

compression - Optional. A string representing the compression to use in the output. Allowed values are ‘gzip’.