The chords aren't in the abc file anyway. I play it in A, sometimes capoed up a notch or two, depending on the singers. Here's the chords reduced to the absolute simplicity. I trust this will help you if you want to transpose it.

I (A)am a true born (D)I_-rish (A)man I'll nev-er de-(E)ny what I a-a-a-(A)am,___
I was (A)born in sweet Tip-per-(D)ar_-y (A)town,Three thou_-sand (E)miles a-(A)way._
Hur-(A)ray me (E)boys hur-(A)ray._No more do I wish for to (D)ro-o-o-(E)oam,___ For the (A)sun
it will shine in the (D)har_-vest (A)time To wel-come poor (E)Pad_-dy (A)home._