A simple command line tool that transforms a json of format: `{"word": count}` to a readable CSV format

json2csv.py

import json, sys
from operator import itemgetter as at
fname = sys.argv[1]
assert fname.endswith('.json')
with open(fname, 'r') as f:
    d = json.load(f)
with open(fname.replace('.json', '.csv'), 'w') as f:
    f.write('{k},{v}\n'.format(k="key", v="val"))
    for k,v in sorted(d.items(), key=at(1), reverse=True):
        f.write('"{k}",{v}\n'.format(k=k.replace('"','""'), v=v))