def __init__(self):
        """
        Creates an instance of the standalone Forward Transfer metric
        """

        self.initial: Dict[int, float] = dict()
        """
        The initial value for each key. This is the accuracy at 
        random initialization.
        """

        self.previous: Dict[int, float] = dict()
        """
        The previous experience value detected for each key
        """

        Creates an instance of the standalone Forward Transfer metric
        
avalanche/evaluation/metrics/forward_transfer.py