list orders doesn't work

[Dinaamagdy]

issue

try to list orders doesn't work as shown if the list doesn't empty

In [50]:  x.order_book.list_my_buy_orders()
---------------------------------------------------------------------------
ResponseError                             Traceback (most recent call last)
/usr/local/bin/js9 in <module>()
----> 1 x.order_book.list_my_buy_orders()

/opt/code/github/rivine/recordchain/JumpScale9RecordChain/apps/orderbook/client/cmds_orderbook_order_book.py in list_my_buy_orders(self, sortby, desc)
     54         args.desc = desc
     55 
---> 56         res = self._redis.execute_command("order_book.list_my_buy_orders",args.data)
     57 
     58 

/usr/local/lib/python3.5/dist-packages/redis/client.py in execute_command(self, *args, **options)
    666         try:
    667             connection.send_command(*args)
--> 668             return self.parse_response(connection, command_name, **options)
    669         except (ConnectionError, TimeoutError) as e:
    670             connection.disconnect()

/usr/local/lib/python3.5/dist-packages/redis/client.py in parse_response(self, connection, command_name, **options)
    678     def parse_response(self, connection, command_name, **options):
    679         "Parses a response from the Redis server"
--> 680         response = connection.read_response()
    681         if command_name in self.response_callbacks:
    682             return self.response_callbacks[command_name](response, **options)

/usr/local/lib/python3.5/dist-packages/redis/connection.py in read_response(self)
    627             raise
    628         if isinstance(response, ResponseError):
--> 629             raise response
    630         return response
    631 

ResponseError: ('unorderable types: NoneType() < NoneType()',)