Matrices over GradedCommutativeAlgebra

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I want to compute the matrix-valued differential forms. But the following code does not work:

R.<dx> = GradedCommutativeAlgebra(QQ)
matrix([dx])

It gives:

NotImplementedError: homomorphisms of graded commutative algebras have only been implemented when the base rings are the same

Is there anyway of computing matrix product with entry values in GradedCommutativeAlgebra?