The entire song seems to just be four notes, but I figured I'd tab it anyways. Not 100% 
sure if it's totally correct, but it sounds pretty good to me!

Best Excuse//Handguns

Intro
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-1010101010101010-55555555-77777777-33333333--|
                  ^switch on the word "best"

Verse
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-1010101010101010-55555555-77777777-33333333--|

Chorus
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-1010101010101010-55555555-77777777-33333333--|

Bridge
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-1010101010101010-55555555-77777777-33333333--|

Outro
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-1010101010101010-55555555-77777777-33333333--|