The melody of I Keep Forgettin’ by Leiber & Stoller runs 205 notes across 22 bars, 1:26 long in Bbm at 110 beats per minute. The tab sits almost entirely in the first two frets, one note at a time — no chords to barre and no strumming pattern to keep up with. A piano backing track plays the chords and bass underneath, so the line you are learning sounds like the record even at half speed.
Prefer to strum and sing it instead? I Keep Forgettin’ chords and lyrics.