>>> from jsonthrift.jsonthrift import JsonThrift
    >>> transport = 'TBufferedTransport'
    >>> protocol = 'TBinaryProtocol'
    >>> thrift_file = 'tutorial.thrift'
    >>> service = 'Calculator'
    >>> method = 'add'
    >>> params = {'num1': 1, 'num2': 3}

    >>> jt = JsonThrift(transport, protocol, thrift_file, service)
    >>> msg = jt.pack_request(method, params, 1)
    >>> response = send_and_recv(msg) # send msg to server, receive response
    >>> result = jt.unpack_response(response)[4]
    >>> print result
    {'success': 4}

    >>> method = 'calculate'
    >>> params = {'logid': 1, 'w':{'op': 4, 'num1': 1, 'num2': 0}}
    >>> msg = jt.pack_request(method, params, 2)
    >>> response = send_and_recv(msg) # send msg to server, receive response
    >>> result = jt.unpack_response(response)[4]
    >>> print result
    {'ouch': {'whatOp': 4, 'why': 'Cannot divide by 0'}}

    >>> # unpack_response returns a tuple, which contains:
    >>> #   message size(TFramedTransport)/None(TBufferedTransport),
    >>> #   message type, will be 2 for thrift REPLY message
    >>> #   method
    >>> #   sequence id
    >>> #   return value