Use a metronome (e.g., 60 BPM) – one double-letter per beat.

For a given sequence of keys [k1, k2, …, kn] , the pattern = k1k1 + k2k2 + … + knkn

Cover your hands; type the entire string without looking.

print(double_pattern(top_row), double_pattern(home_row))

It looks like the string qqwweerrttyyuuiioopp aassddffgghhjjkkll is a repeated pattern of adjacent keyboard keys (QWERTY layout) — specifically, the top row and home row typed in pairs.