Interface Inherited declaration

Question

I'm trying to use an old code which has been developed by a Github developer. The code uses implements in zope.interface library to declare interfaces on a class's elements. Since implements in the library doesn't work anymore at Python 3.6, I confront with this error:

TypeError: Class advice impossible in Python3.  Use the @implementer class decorator instead.

Several websites have explained how to substitute implements with @implementer to work at Python 3.6, like here. But I haven't found any example to explain how to update the code when zope.interface.implements has been used as an inheritance. The code looks like this:

from zope.interface import implements
class Car(implements(Moveable)):
     def __init__(self, x, v, lane, model: IDM, lane_change: LaneChange,
             length):
...

I would like to update this code to work at Python 3.6. I've tried this

@implementer(Moveable) 
class Car:
     def __init__(self, x, v, lane, model: IDM, lane_change: LaneChange,
             length):

but it does n't work. Please help me to figure out how to make the above code running in Python 3.6.

score 3 · Accepted Answer · answered May 06 '20 at 17:45

3

Below steps solved the issue for me,

pip uninstall apex
git clone https://www.github.com/nvidia/apex
cd apex
python3 setup.py install

answered May 06 '20 at 17:45

Shankar Ganesh Jayaraman

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score 2 · Answer 2 · answered Jun 20 '19 at 12:28

To use implementer instead of implements as suggested by Python, you need to import it as well opposed to importing implements

from zope.interface import implementer

In your code it shows you are still using implements, that seems to be the problem according to provided information. Hope it helps.

Interface Inherited declaration

2 Answers2