need expert confirmation.  

Python 2.7: http://docs.python.org/2/library/json.html#encoders-and-decoders
json string -> python unicode

Python 3: http://docs.python.org/3/library/json.html#json-to-py-table
json string -> python strr

  http://docs.python.org/3/library/json.html#json.loads

json string -> python