@abstractmethod
def __len__(self):
    'Length of the discrete-time solution\n\n        Corresponds to the number of filtering/smoothing steps\n        '
    raise NotImplementedError
Length of the discrete-time solution

Corresponds to the number of filtering/smoothing steps
@abstractmethod
def __len__(self):
    'Length of the discrete-time solution\n\n        Corresponds to the number of filtering/smoothing steps\n        '
    raise NotImplementedError