Darren did not play "The World Is a Bitter Place, and I Am No Longer Afraid to Drive" by Snowhaus so why would he list it if he didn't play it. The guy who filled in for him picked that song as a mystery song on last week's show.
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Now if you meant that last week's playlist still says mystery song and needs to be updated, maybe you should have just posted that on last week's show page.
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RandomSauce:
The other mystery song answer is not on the playlist.