Assigning a metaclass to a class by the use of the __metaclass__ keyword was deprecated in Python 3.0, and as of Python 3.5 its use can break code.
The correct way to add a metaclass to a class in Python 3.0+ is this way:
class MyAbstractTask(object, metaclass=ABCMeta):
....
ashleysommer
commented
6 years ago
Assigning a metaclass to a class by the use of the
__metaclass__keyword was deprecated in Python 3.0, and as of Python 3.5 its use can break code. The correct way to add a metaclass to a class in Python 3.0+ is this way: