def METHOD_NAME(self, dim: int) -> LinearOperator:
    if torch.is_tensor(self.base_linear_op):
        base_linear_op = self.base_linear_op.unsqueeze(dim)
    else:
        base_linear_op = self.base_linear_op.METHOD_NAME(dim)
    res = self.__class__(base_linear_op)
    return res