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Solve the following problem using Python, implementing the functions described below, one line at a time
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Description:
 def mask_reduce(mask):
 """Reduce a boolean mask, removing all false slices in any dimension. Parameters mask : ndarray with bool dtype The mask which is to be reduced Returns ------- A boolean mask with no all False slices. """

    mask = mask.copy()
    for i in range(len(mask.shape)):
        a = mask.copy()
        j = list(range(len(mask.shape)))
        j.remove(i)
        j = tuple(j)
        a = a.max(axis=j, keepdims=True)
        idx = [slice(None)] * len(mask.shape)
        a = a.flatten()
        idx[i] = [k for k in range(len(a)) if a[k]]
        mask = mask[tuple(idx)]
    return mask