Linear code over a finite ring

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The command

LinearCode(M)

works well on a Finite Field F, but doesn't work for a finite ring. Is there any way to construct a linear code over a finite ring using sage? In other words, could we construct a module over ZZ/nZZ? I try to understand the trac tickets #6452 and #19345 for constructing a linear code over a finite ring. Unfortunately, I failed to understand.