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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 tran3(self, a, b, c, n):
 """Get accumulator for a transition n between chars a, b, c."""

        return (((TRAN[(a+n)&255]^TRAN[b]*(n+n+1))+TRAN[(c)^TRAN[n]])&255)