As Matt E. suggestedsuggested in the comments to Thomas's answer, if you do keep the answer, put a note at the top of your answer indicating to the OP that your answer is similar to another answer, so that they don't waste time reading both before figuring out that they are essentially the same. This saves wasted effort on the OP's part, but at the same time doesn't make the effort you put in totally useless.
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