Direct sum for tensor product of CombinatorialFreeModule

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Problem: Given a finite free resolution C of $\mathbb{Z}$ over $\mathbb{Z}G$ I would like to consider the free resolution $C \otimes C$. Then of course in this new resolution I'm going to have direct sums of tensor products. In sage I'm working with CombinatorialFreeModule, there is a way to defining a direct sum over CombinatorialFreeModule_Tensor?

Thanks in advance.