'imarray' object has no attribute '_imarray__dimension'

[Ek-Ram]

Hi,
I am trying to this code but I get this error :

line 70, in convolve
    if len(mask.shape) != len(self.__dimension):
AttributeError: 'imarray' object has no attribute '_imarray__dimension

Knowing that the only change that I made is changing : switching toscipy.imageio.imreadsince scipy.misc.imread is deprecated.
Thank you, for helping me.